candle and rising water experiment

Posted on Last updated: December 8, 2021 By: Author Kim

Categories STEM Activities

Rising Water Experiment – Magic Water Science Experiment

Rising Water Experiment: a magic rising water science experiment.

• Ages: Preschool , PreK , Kindergarten, Elementary
• Difficulty: Easy
• Learning: STEM , Air Pressure, Ideal Gas Law, Charles’s Law

Did you know you can make water rise without touching it?

Nope, it isn’t magic. It’s science. Surprisingly simple science in fact. This science experiment comes together in minutes, but it will captivate your children.

Here is how to do the raising water experiment, simple glass and candle STEM magic.

What's In This Post?

Supplies for your Glass and Candle Experiment

How to do the rising water experiment, the science, the chemical component, the physical component, the big picture, what should children take away from this science experiment, conservation of matter, charles’s law, ideal gas law, ask a question, magic water science experiment, free printable raising water experiment instructions, instructions, rising water experiment.

This experiment uses at-home materials and is fascinating! It does require adult help, but adults will love it too.

You only need a few items to make this magic water STEM experiment work. Here is what you need to gather up:

• Glass or Jar
• Small Votive Candle
• Shallow Dish
• Food Coloring (Optional)
• Matches or Lighter

Before we even get started please remember that an adult needs to be present for this experiment. We are using fire, which can be dangerous, so be smart.

Step 1: Take a sallow dish and fill it with water. You want just enough to cover the bottom.

Step 2: If you want, add food coloring to the water. This just makes it easier to see and is fun, so totally optional.

Step 3: Place your small votive in the middle of the dish.

Step 4: Light the candle, then quickly place the empty glass over the flame, touching the water. Now wait while the candle burns out.

Step 5: Watch as the water rises up into the glass!

The number one safety tip here is to be careful with the flame! This experiment must be done with adult supervision at the bare minimum. With younger children, like preschoolers, this needs to be an adult-led experiment.

This STEM activity also uses glass, so it is a good idea to be careful in case it falls or breaks.

Clean-up for this activity is pretty simple. Slowly lift the bottle off of the candle.

Once the bottle is off, gently blow the candle out. Let the candle cool (or have an adult get it), remove it from the dish, and dump the water down the drain. That’s it!

More must do activities!

How the Rising Water Experiment Works

This is a pretty cool experiment, but it is important to talk about what actually makes this happen. It’s fun to say it is magic, but as my kids tell me, ‘It’s better. It’s science.’

There are two main components of this experiment that cause the water to rise, a physical component and a chemical component. These two components work together to make this experiment happen.

The candle burning creates a chemical reaction. The flame burns both the paraffin (candle wax) and the oxygen under the glass. This reaction uses up oxygen and creates water and carbon dioxide as a result. Twice as much oxygen is burned than carbon dioxide produced, so the volume of air in the glass decreases.

(Note the total amount of matter in the jar remains the same. Conservation of matter tells us this. But some molecules are larger than others and take up more space in terms of volume.)

The physical component is why the water level in the glass doesn’t rise as soon as the candle is covered. The candle warms the air, and this increases the air volume inside the glass.

When the candle burns out (because all the oxygen is used up), the temperature cools quickly. This temperature decrease means the volume also decreases, which lets the water rise to fill up that space. This is called Charles’s Law.

Charles’s Law tells us that the ratio of volume to temperature must remain the same, so if one goes down the other goes down too.

These two parts of the experiment work together. Both the volume change and temperature also affect the pressure in the system we created. When temperature decreases (the physical component) and the size of the matter decreases (the chemical component), the pressure of the gas inside the glass decreases too.

This lower pressure inside means the water can rise as well. This is explained by the Ideal Gas Law.

The idea of air pressure can be a bit challenging for young children to understand. It isn’t something they can clearly see, so that makes sense. But they can understand something changing size, in other words when volume changes.

If the air inside the glass takes up less space, it makes sense for the water to fill in that space and rise inside the glass.

I understand that we went over a lot of more complicated concepts here. (And don’t worry, I’ve listed the definitions for the terms below to help out.) Am I really expecting young kids to understand and retain all this?

No. I mean, it would be cool if they did. And some might. But realistically that is not the point of this kind of science. The purpose of giving these explanations is so that you as a caregiver can quickly get the reasoning behind this project and interpret it for your children.

It is helpful for your children to see these experiments. Even if they don’t fully understand the details, this experience is adding to their understanding of how the world around them works. It builds their science base.

Using the vocabulary helps kids as well. First, it gives new words which are always helpful for communication skills. But I think, more importantly, it demystifies science later in life. Science can feel like a whole new language as we get older, and that can be very intimidating. If we have been exposed to these terms though, it’s less scary. We might not know exactly what they mean but we know that we have heard them before. This helps kids feel like science belongs to them. Because it does.

Helpful Definitions

Here are a few helpful definitions for the raising water experiment.

The conservation of matter law states that matter is not destroyed or created. It can change forms, but the total amount stays the same.

Charles’s Law tells us that the volume of a gas is directly proportional to the temperature of the gas. As the volume decreases, the temperature decreases, for example.

The Ideal Gas Law describes the conditions a gas is under and how those conditions will vary as compared to each other. The pressure of the gas multiplied by the volume will always equal the number of moles multiplied by the temperature and ideal gas law constant.

The Scientific Method

Since an adult is needed to run do this experiment with kids (fire safety!), it is a great time to talk through the scientific method! Here is a guideline of what that can look like with this STEM experiment.

(And don’t forget to learn all the life lessons that come along with the scientific method here: Beyond the Science- What Kids Are Really Learning .)

Ask your child, what do they think is going to happen when we put the glass on the candle? The key here is to listen and let them think it through. No answer is too far out there or wrong at this step.

The observation step is key throughout any experiment, but take a moment and look at their components. What do they notice about them? How do they normally behave? What do they already know about them?

Narrow down your potential answers and decide on one or a couple of outcomes you think are most likely. This is your hypothesis.

Time to run the experiment! Encourage your children to keep watching what is happening. (In this particular observation, sight is going to be the key thing to focus on. Some touch is possible, watching out for the flame of course. And you can encourage smell and hearing for practice.

What did they observe? Now is the time for them to tell you everything they can about what just happened.

This is where we form the conclusions and apply the information we learned. Do they think this will always happen? How did the results match or differ from their hypothesis?

Real experiments always lead to more questions. What does your child want to try next? What would they change in the experiment? Does more water in the dish change anything? Can they try to suck up all the water? Would adding a different liquid change the results?

Even if you aren’t able to complete any of their additional experiment ideas, it is a good idea to think of ways to explore more. Plus it is amazingly fun to hear all the ideas kids have.

This is a great experiment to do over and over. It’s fast, cheap and full of fun learning. It’s a must-do!

Let’s find your next fun activity!

Raising Water Experiment

How to do the raising water experiment that will wow kids!

• Food Coloring (optional)
• Lighter or Matches
• Fill your shallow dish with enough water to cover the bottom. Add food coloring. (optional)
• Place your votive in the middle of the dish.
• Light the votive candle.
• Place the glass upside down over the candle.
• Wait for the candle to burn out and watch the water rise!

This is a science experiment that needs adult supervision and help. It uses fire and needs an adult to be safe.

To clean up, gently pull the glass off the candle. Make sure the candle cools and the water can go down the drain.

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Getting the facts right

Photos of the experiment

An exhibit of explanations

What do we learn, appendix: the chemical equation for general n.

Appendix: the ideal gas equation

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Rising Water Experiment

Light a fire under middle school science and heat it up! Place a burning candle in the water and watch what happens to the water. Explore how heat affects air pressure for an awesome middle school science experiment. This candle and rising water experiment is a great way to get the kiddos thinking about what is happening. We love  simple science experiment s; this one is super fun and easy!

CANDLE IN WATER EXPERIMENT FOR KIDS

CANDLE IN WATER

This candle experiment is a great way to get your kiddos excited about science! Who doesn’t love watching a candle? Remember, adult supervision is required, though!

This science experiment asks a few questions:

• How is the candle flame affected by placing a jar over the candle?
• What happens to the air pressure inside the jar when the candle goes out?

Our science experiments have you, the parent or teacher, in mind. Easy to set up, and quick to do, most activities take only 15 to 30 minutes to complete and are heaps of fun! Plus, our supplies lists usually contain only free or cheap materials you can source from home.

Make sure to check out all our chemistry experiments and physics experiments !

SCIENCE EXPERIMENTS FOR KIDS

Science learning starts early, and you can be a part of that by  setting up science at home  with everyday materials. Or you can bring easy science experiments to a group of kids in the classroom!

We find a ton of value in cheap science activities and experiments. All our science experiments use inexpensive, everyday materials you can find at home or source from your local dollar store.

We even have a whole list of kitchen science experiments , using basic supplies you will have in your kitchen.

You can set up your science experiments as an activity focusing on exploration and discovery. Make sure to ask kids questions at each step, discuss what is happening, and discuss the science behind it.

Alternatively, you can introduce the scientific method, get kids to record their observations and make conclusions. Read more about the  scientific method for kids   to help you get started.

Click here to get your free printable STEM activities pack!

CANDLE IN A JAR EXPERIMENT

If you want to extend this science experiment or do it as a science fair project using the scientific method , you need to change one variable.

EXTEND THE LEARNING: You could repeat the experiment with different size candles or jars and observe the changes. Learn more about the scientific method for kids here .

• Middle School Science
• Elementary Grades Science
• Tea light candle
• Bowl of water
• Food coloring (optional)

INSTRUCTIONS:

STEP 1: Put about a half inch of water into a bowl or tray. Add food coloring to your water if you like.

STEP 2: Set a tea candle in the water and light it.

ADULT IS SUPERVISION REQUIRED!

STEP 3: Cover the candle with a glass, setting it in the bowl of water.

Now watch what happens! Do you notice what happens to the level of water under the jar?

WHY DOES THE WATER RISE?

Did you notice what happened to the candle and then to the level of the water? What’s happening?

The burning candle raises the temperature of the air under the jar, and it expands. The candle flame uses up all of the oxygen in the glass, and the candle goes out.

The air cools because the candle has gone out. This creates a vacuum that sucks up the water from the outside of the glass.

It then raises the candle up on the water that enters the inside of the glass.

What happens when you remove the jar or glass? Did you hear a pop or popping sound? You most likely heard this because the air pressure created a vacuum seal, and by lifting the jar, you broke the seal resulting in the pop!

MORE FUN SCIENCE EXPERIMENTS

Why not also try one of these easy science experiments below?

Click on the image below or on the link for more fun science experiments for kids .

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Rising Water Experiment Step by Step

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This is a super fun and exciting way to learn about the properties of air pressure by watching water get pulled into an upside-down jar! This science experiment only requires a few household items along with adult supervision. Here is how to do the Rising Water Experiment Step by Step.

Get more fun and easy Atmospheric Pressure Experiments here!

PIN THIS EXPERIMENT FOR LATER

The best thing about this gravity defying science experiment is that it takes less than 10 minutes to gather up your supplies to start learning while having fun!

Table of Contents

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Supplies Needed:

• Clear glass jar or cup
• Box of matches
• 1 Bottle cork (or a candle)
• Food coloring (optional)

How to Make Water Rise in a Jar

• Cut the cork in half lengthwise and poke 3 holes in it for the matches to fit. (Skip this step if you are using a candle)
• Fill the plate with water and place the cork (or candle) in the middle
• Place your match platform or candle on the plate and ignite them
• Place the jar or glass upside down over the flame and let it rest on the plate
• Watch as the flame goes out and the water rises in the glass!

Step 1: Get the cork or candle ready

Depending on the materials you have available for this, you can use a bottle stopper cork, a candle, or even a small block of wood. The idea is that you need a safe platform for your flame to sit on in the water.

I didn’t have any candles at home, so I opted to use a cork bottle stopper that had a round wood piece at the end. You can pull the round wood piece off pretty easily and even use the wood piece for your match platform.

Using the round wood piece I then used a power drill on a small drill bit (about 3/32″) to drill 3 small holes in the cap. These holes should be a snug fit to hold your match sticks upright when the round wood cap floats in the water.

Another way to create this platform for the matches is to cut the cork in half lengthwise from top to bottom. Then use a pen to poke 3 holes for the matches into the soft cork.

The easiest way would be to just stick a candle onto the middle of the plate and then fill the plate with water. Since I didn’t have a candle and tend to do things the hard way, I went with using the round piece of wood from the cork.

You could also use a little block of scrap wood and drill holes into it. The important part is that it floats and will keep your matches out of the water.

Step 2: Fill your plate with water (and add some color if you want to)

I am a little bit obsessed with using food coloring and anytime I get the chance to add a little color to the water in these experiments I go for it! So if you want to add your favorite color to the water now is your chance!

The easiest way to do this is to fill your jar about halfway full of water. When you add the food coloring you can give the jar a little twist. Then pour the water onto your plate and the coloring should be mixed in.

Adding food coloring to your water will help the water be more visible when it gets sucked into the jar, but this experiment will also work completely fine with plain old clear water too!

Step 3: Place your match platform or candle in the water on the plate and light them

Now the fun is really starting to heat up, but before we go any further remember that adult supervision is required from here on out since we are working with fire!

Go ahead and grab and candle and stick it in the middle of the water-filled plate. If you are using a makeshift match platform like me, push three matchsticks into the holes in your platform and place it in the water.

Note: If you are using a cork that was cut in half, you will need to carefully balance the placement of your matches to prevent them from tipping into the water and being extinguished.

Use another match or a lighter to light your fire device of your choosing. If you are using matches for your “floating flame” you need to hurry on to the next step before they burn out. If you are using a candle then you can take your time moving onto the next step.

Step 4: Tip your empty jar upside down over the flame on the plate

Now it’s time to witness some crazy cool science in action! Grab your jar or clear glass and gently, but quickly turn it upside down and set it on top of the burning flame.

Go ahead and move your hand from the jar (the jar might get a little hot) and let it rest on the water-filled plate. This is the part you don’t want to miss!

Step 5: Watch the flame go out as the water rises in the jar

You should see the water slowly rise in the jar as the flame is still burning, but after a second or two the flame will go out and the water will rapidly rise into the jar.

After another second or two the water will stop rising but will stay at that level until the jar is pulled from the plate.

Why does the flame go out when you put a jar over it?

When a jar or glass is placed over the flame, the flame can only burn for a few seconds before running out of oxygen. Fire needs oxygen to burn and once all the oxygen inside the jar is burned up, the fire will go out.

How does the water rise inside the jar?

As the fire in the jar rapidly heats up the air inside the jar, the air molecules start moving faster increasing the air pressure. Some air escapes between the jar and the plate as the pressure pushes it out.

As soon as the flame runs out of oxygen and is extinguished in the jar, the very hot air rapidly cools and contracts and the pressure drops quickly. This lower pressure inside the jar is imbalanced between the relatively higher pressure on the outside of the jar.

Does air pressure make the water rise in the jar?

Yes, the lower pressure inside the jar in partnership with the higher pressure pushing down on the plate of water causes the water to fill the empty space in the jar. The water will rise until the pressure on the inside of the jar and the outside become equal.

Try mixing it up:

An interesting variable to try with this experiment is to use cold water and then do it again using hot water. Did you notice any difference?

What happens if hot water is used in the rising water experiment?

The rising water in the jar experiment should work with either hot or cold water, but I did notice the hot water does not get quite as high in the jar.

This is because the warmer water keeps the air in the jar from cooling down as fast as it can with the cold water once the flame goes out. Since the air doesn’t cool as fast with the hot water in the jar, the pressure doesn’t drop as low and the water doesn’t get pulled as strongly into the jar.

Can water rise out of the ocean into a hurricane?

Yes, this experiment is a great way to explain how storms work and especially how hurricanes can gain enough strength to actually pull water from the ocean up into the center of the storm.

This is possible thanks the sun providing uneven heating of the air on the earth. As warm air is heated by the sun it rises and becomes less dense. The cooler, high-density air begins to move to take the place of the warm air.

This cycle continues to repeat and is part of the process of creating high and low-pressure weather systems. The stronger the pressure difference (pressure gradient) is between a low-pressure system and a high-pressure system, the faster the wind speeds will generally be!

If the pressure drops low enough and the wind is strong enough (like in a hurricane) then the water can actually be lifted up and out of the ocean just like it was lifted into the jar in our experiment!

More Easy Science Experiments for Kids:

• Upside Down Glass of Water Experiment
• Floating Orange Experiment
• Baking Soda and Vinegar Balloon Experiment

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Burning Candle Rising Water Experiment

• December 3, 2020
• 5-6 Year Olds , 7-9 Year Olds , Chemistry , Fire Science , Physics , Rainy Day Science

In our previous experiment , we discussed the candle covered with glass. The basic science behind was the oxygen limitation that made the candle go off.

In an extension of that science activity, I am now going to share another experiment with you. It is also to do with candles and glass, but with a twist.

Apart from the oxygen limitation that puts the candle off, there is also low pressure created in the glass that leads to a vacuum.

This will cause some effects and that looks like magic to kids but the science to all adults. So let us do this magic to our kids and also explain them some science.

Things required

• Ceramic or glass plates
• Glass tumbler
• Matchbox with stick

Steps involved

Fill the plate with water.

Place the candle on the plate and lit it. You can see the candle glowing brightly.

It may float or stand on the water in the plate based on the weight of the candle.

The presence of water does not make any difference to the candle at this stage.

After sometime invert the glass tumbler and place it on the glowing candle.

Imagine the glass will close the candle. In a few minutes, you can witness candle blowing off as the closed glass limits oxygen in the space surrounding the candle.

Another thing you will witness is now the water in the plate enters the glass and you will see the level rising constantly.

Science Behind Candle Rising Water

The basic science here is the lack of oxygen puts off the candle in step 2. At the same time lack of oxygen also lowers the atmospheric pressure and creates a vacuum.

This leads to the water entering the glass from the plate. You can see this like the water level rises in the glass.

Detailed science with chemical equations

The water level rises to 1/10th of the glass before the candles go off is importantly you must note.

There is no air bubble formed. The water level will stay for few minutes once the candle goes off completely.

So both the candle dies out and water rises happens concurrently.

Chemical equation

Oxygen + Candle (wax/paraffin) à Water and Carbon dioxide

O 2 + C n H 2n+2 à H 2 O + CO 2

I have an exercise for older kids here. Yes, ask your older kids to balance the chemical equation taking n as 1. Post the answers for learning.

The oxygen is 2 times more than the carbon dioxide released and hence the air volume reduces.

Let me also explain the physics behind this experiment for physics fans!

Physics facts

The burning candle produces heat which heats the air and thus expansion happens. This will cancel the oxygen depletion slowly and the water level remains down.

When oxygen gets saturated in the glass the candle goes off and the air begins to cool and volume decreases.

The reduction in air pressure will create a vacuum and hence water level rises.

Also, water initially is in the gas state when there is heat around and later it condenses and rises in level as water.

The same process or science is applied to how storms and hurricanes are formed.

When the sun heats up the air causing its density become low which is the reason for formation of wind and storms.

The high density air moves into the lower density air pockets. When there is enough wind referred to as ‘hurricanes’ causing the water rise and lifted up out of the ocean.

• This experiment is magic for kids aged 3 to 5.
• You can teach some science to kids 5 – 8 as they will know about oxygen etc.
• 8 -12-year-old kids can benefit from the chemical equations and the detailed science of this experiment.

As I always alert you, please make sure to assist or monitor kids when they do this experiment.

It involves fire and you must be around to avoid any accident. Also, dealing with glass dishes needs support which you must provide.

Depending on the age of your kid you decide whether you must take their help or help them or just be around. However, we advise you to be present irrespective of the kid’s age.

Interested in More Air Pressure Experiments? Explore the list below

DIY Drip Drop Water Bottle

Balloon Powered Car

Make a Balloon Rocket

We have tried answering a few usual questions that might arise in the kid’s mind. My little one always ask questions upon which I fumble many times. So here you go with ready-made answers as well.

Twice the time of oxygen is burnt than the available CO2 that decreases the air pressure and hence water level rises. The air cools soon after flames go off and the molecules slow down making the water vapor condense to moisture.

The heat of the flame will start melting the wax near the wick and the liquid wax is drawn up to the wick due to capillary action. The flames heat will vaporize the wax and break them into molecules of oxygen and carbon.

The candle is put off by placing the lid on the candle that is lit. It is another way to extinguish the candle. The lid is placed on the flame which immediately cuts off the oxygen and thus puts off the candle.

The wick gets close to the glass the wax burns off and heats the glass. This might lead to the explosion of the glass. However, when water is kept on the glass this explosion is prevented.

As long as the pressure is low the water rises and when the pressure level equalizes the water level stops rising.

Place the glass flat on the plate to prevent air bubble forming. In case if it is tilted, then the air bubbles will form due to the difference in the pressure level between the inside and outside surface.

When you observe the tall and short burning candles closed with a glass container, surprisingly the tall candle goes out first because the carbon dioxide released travels upwards and suffocates the tall candle making the cold air sink. The short candle utilizes the oxygen in this cold air and stays on for some more time. When all the oxygen is used up, the short candle also dies.

Yes, place a candle in the bowl containing water and lit it. Slowly it goes down melting the wax which forms a protected wax around the wick. This allows the candle to stay on for good amount of time even though the flame has reached the level lower than the water. And of course, after a while water gets into wick and turns the flame off.

Modifications you can try with this experiment

 Here are the few variations to further explore the scientific concepts in this experiment.

• Change the amount of water taken in the plate and observe how does it affects the water level rise.
• Discuss on what happened to the water when the candle is lit.
• How does temperature changes happen when we use different types of colored water?
• You can use colored water made of food coloring, milo, liquid dyes, powdered dye etc.
• Experiment on hot water versus cold water and observe the temperature and air pressure changes.
•  Also try the experiment using two candles versus one candle or more candles etc.
• Use different liquids instead of water and check what are the changes and results.
• Try with different candle weight and height
• Change the glass to narrow and broad
• Make colored water and also increase/lower the water level in the plate
• Try not to lit a candle before and light it only after placing the glass. Yes, you need to lift it a bit and light it. Preheating is avoided to observe for any changes in the results.

Share the results with us that will let all our readers know what happens with all these modifications. In the meantime, I will also try different twists with my kids and post my experience.

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Why Does the Water Rise?

A candle and some rising colored water reveal a hidden property of air that’s around you all the time.

Print this Experiment

Watch closely and use everything you know about air pressure differences to explain the mystery of the rising water. Look for clues that explain why the water rises into the container. It may not be what you think it is so keep your eyes open as you collect data. The best part is that you’ll likely have to do the experiment several times to confirm how air pressure is involved.

Experiment Videos

Here's What You'll Need

Plate or shallow dish, clear, slender container, 1 cup (237 ml) of room temperature water, food coloring, adult supervision, let's try it.

Add 2-3 drops of food coloring to the water. This will make the movement of the water easier to see later. It’s interesting to watch how the drops of coloring spread through the water before stirring it.

Pour the colored water into the plate. You want about a half-inch (1 cm) deep puddle in the plate. More is OK.

Set the candle straight up in the puddle in the center of the plate. To make sure everything will fit, place the slender container over the candle and into the water. Make sure its base is well above the candle wick and its top edge is submerged under the water. Add water if needed. When you’re happy with the setup, remove the container.

When the candle is stable, the water is calm, and an adult is present, light the candle. The candle flame needs to burn brightly.

There’s no need to rush this Step; there’s a lot to watch anyway. Turn the container over again and lower it over the burning candle. Place the container on the plate in the water and let go but don’t take your eyes off of the water level inside it. You may see bubbles coming from inside the container. At first, the candle stays burning and the water level rises slowly. About the time the candle goes out, the water rises quickly. This is the mystery: why does it rise?

Repeat the procedure several times so that you can write or draw an explanation as to why the water rises. HINT: The difference in air pressure inside and outside the container is important.

How Does It Work

A common misconception is that the consumption of oxygen by the flame in the container is a factor in the water rising. There may be a slight possibility that there would be a tiny rise in the water from the flame using up oxygen but it’s extremely small compared to the actual reason. Simply put, the water would rise imperceptibly at a steady rate as the oxygen were consumed. You likely saw the level rise almost all at once and pretty much after the flame went out.

At first, the flame heats the air inside the container and this hot air expands quickly. Some of the expanding air escapes from under the vase where you might have seen some bubbles. When the flame fades and goes out, the air in the container cools and cooler air contracts or takes up less space. That contraction creates a weak vacuum – or lower pressure – in the container. Where’s the higher pressure? Right! It’s outside the container pressing down on the water in the dish. The outside air pushes water into the container until the pressure is equalized inside and outside the container. The water stops rising when that pressure equalization is reached.

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Rising Water Experiment

We normally don’t play with fire (for obvious reasons).

But here is a experiment I didn’t expect to be so easy and so much fun to do.

At the same time, the results are so hard to understand, with, sadly,  much misleading information  on the internet.

As always, adult supervision is required !

THERE IS FIRE INVOLVED

This is an easy rising water experiment. While your child may not understand completely the real science behind this experiment, it is still an awesome science activity to do to spark their interest in STEM!

• votive candle
• food coloring (optional)
• deep dish or container
• a tall glass
• adult supervision

Instructions

Rising water experiment step by step.

• Fill the dish or container with water to about 1 inch deep.
• Add food coloring into the water for better visual results (optional).
• Place a candle in the middle of the water. Make sure the water is at least an inch below the top of the candle.
• Light the candle.
• Invert the tall glass.
• Slowly and vertically, lower the glass to completely cover the candle.
• Watch the candle extinguish and water level rise.

Candle experiment explanation

Initially, you could see the water level rising a little bit while the candle was burning. But after the candle had gone out, the water level kept rising for almost an inch above the water level outside of the glass and stayed there.

So what do you think happened?

Did you try this project?

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The first thought in most people’s minds is that the candle burned and used up oxygen. There was less oxygen left in there.

However, when the candle burned, it also gave out carbon dioxide, which was another gas that could replace the volume previously occupied by oxygen. Shouldn’t the volume have stayed the same then?

To figure out what happened, it helps to understand a little bit of chemistry .

2 O 2 + C H 4 = C O 2 + 2 H 2 O

As you can see,   during burning, two oxygen molecules result in one carbon dioxide molecule and two water molecules . So the air volume decreases .

But if this was the main cause, shouldn’t the water level have stopped rising after the candle fire went out?

Turns out that besides chemistry, there is also a physical aspect that causes a big change in air volume .

After the candle went out, the air cooled. Cold air is more dense  and occupies a smaller volume than hot air. At the same time, water vapor (result of burning) condensed when the air cooled further reducing air volume inside the glass. Therefore, the water level rose even after the fire was out.

Another physical aspect contributing to the phenomenon was that the air surrounding the fire was initially hot before the glass was placed around it. So we started with air that was already less dense. Starting with less air than the outside added to the shrinkage in volume when the air cooled.

For the science-inclined minds, here is a detailed technical and scientific analysis  of this experiment.

See, you can learn so much about science from one little experiment. Isn’t it amazing?

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Burning Candle, Rising Water Experiment

Introduction: Burning Candle, Rising Water Experiment

I saw a short video of this experiment on Reddit and thought it would be an interesting science experiment to try with the kids.

Here is our recreation of the experiment:

Step 1: Materials

Below is a list of the materials you will need for the experiment.

• Tall Glass with a slightly larger diameter than the candle
• Food Coloring or Mio
• Spoon (Optional)

Step 2: Add Food Coloring to Water

You can do the experiment with just water but colored water is easier to see. We used Mio instead of food coloring.

Step 3: Add Colored Water to Plate

You should experiment with different levels of water. We used about 1/4".

Step 4: Place Candle in Center of Plate

Candle should be placed vertical as shown.

Step 5: Light Candle

Light the candle. Note that a larger flame gives a more dramatic effect.

Step 6: Place Glass on Candle

Carefully place the glass container over the candle.

Step 7: Watch the Science in Action

I tried to grab some frames of the process. Notice how the colored water moves from the plate into the glass container. Once the candle flame goes out, you will see an inrush of water.

If you search for this on the web, you will see multiple ideas on how it works.

I took the explanation of Oliver Knill from the Harvard Math Department. He states in general terms: "The candle heats the air and expands it. This cancels the depletion of the oxygen temporarily and the water level stays down. When the oxygen is depleted, the candle goes out and the air cools. The volume of the air decreases and the water rises. The temporary temperature change delays the rise of the water"

For debate on the subject, see the following link:

math.harvard.edu

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Rising Water

Try this fun experiment with candles, air and water. Isn’t it amazing that air pressure can cause water to rise and climb the inside of a glass?

• Food colouring
• A tea candle
• A glass or an Erlenmeyer flask with an opening larger than the candle

Instructions

• An adult should help with this experiment
• Pour a little water onto the plate and add some food colouring. The water should cover the bottom of the plate and climb up the sides
• Light the tea candle and place it in the middle of the plate
• Hold the candle over the tea candle for a few seconds, ensuring that the air inside the glass is heated
• Place the glass on the plate over the candle
• Watch as the flame is extinguished and the water rises in the glass

What happens?

The air inside the glass expands when it is heated. This causes some of the air that was inside the glass to be pushed out. The air gets cool again when the flame is extinguished, which leads it to shrink and occupy less space inside the glass. Now the air pressure inside the glass is lower than outside. The air pressure outside the glass pushed the water. This is why it rises in the glass.

Try this fun experiment with candles, air and water. Isn’t it amazing that air pressure can cause water to rise and climb the inside of a glass? Equipment A plate Water Food colouring A tea candle Matches A glass or an Erlenmeyer flask with an opening larger than the candle Instructions An adult should help….Click to read more

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– plate with raised rim ro bowl – water – candle – ligther or matches – mason jar or glass – food coloring  – playdough

Get ready to WOW your kids with a super EASY science experiment for kids !  This simple rising water experiment  uses common household items to demonstrate a couple scientifc principles .

This  burning candle in water experiment  is fun for kids of all ages. Includes free printable burning Candle in Water Experiment Worksheets  as they explore  why does the water rise in the candle experiment .

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Why does the water rise?

It's a very popular experiment ( eg ), from elementary school : put a burning candle on a dish filled with water, cover the candle with an inverted glass: after a little while, the candle flame goes out and the water level inside the glass rises.

The standard explanation (as I recall it) was that combustion "burns" oxygen, and the consummed volume accounts for the extra water that goes inside the glass. Is this correct? I remember feeling (years later) uncomfortable with the explanation, because "to burn" is certainly not "to dissapear": I thought that oxygen combustion produces (mainly) $CO_2$ and hence one oxygen molecule would produce another $CO_2$ molecule, and the volume would remain basically the same. Perhaps $CO_2$ dissolves into the water? I would doubt that.

To add to my confusion, others state that the main cause is not the oxygen combustion but the changes of air temperature, that decreases when the flame goes out and makes the air inside the glass contract... which would rather invalidate the experiment as it was (and is) traditionally taught to students.

What is the right explanation?

(image from here )

Update : As from webpage linked in accepted answer, there are several effects here, but it's fair to say that the "traditional" explanation (consumption of oxygen) is wrong. Oxygen (plus paraffin) turn into $CO_2$ (plus water) (a representative reaction: $C_{25}H_{52}+38O_2 \to 25CO_2+26H_2O$ ). This would account for a small reduction in volume ( $25/38 \approx 2/3$ ), even assuming that this is the complete chemical picture (it's not) and that water condenses ( $CO_2$ dissolves in water poorly and very slowly). The main cause here is thermal expansion-contraction of air.

• home-experiment
• physical-chemistry

• $\begingroup$ Is there a stackexchange for chemistry? Maybe they could provide better help. $\endgroup$ –  Lemon Commented Jan 4, 2012 at 1:58
• $\begingroup$ @jak Not yet. $\endgroup$ –  Manishearth Commented Mar 15, 2012 at 7:21
• $\begingroup$ @Manishearth Yes there is - chemistry.stackexchange.com It is in beta, though. $\endgroup$ –  Dave Coffman Commented Jul 28, 2014 at 22:06
• $\begingroup$ @DaveCoffman look at the date on that comment. I moderate Chem.SE, I know about it :P $\endgroup$ –  Manishearth Commented Jul 28, 2014 at 22:28
• $\begingroup$ Geez - Sorry about that. $\endgroup$ –  Dave Coffman Commented Aug 2, 2014 at 18:19

3 Answers 3

I found two web pages that explain the phenomenon quite well, and even looks into the misconceptions people have.

The candle flame heats the air in the vase, and this hot air expands. Some of the expanding air escapes out from under the vase — you might see some bubbles. When the flame goes out, the air in the vase cools down and the cooler air contracts. The cooling air inside of the vase creates a vacuum. This imperfect vacuum is created due to the low pressure inside the vase and the high pressure outside of the vase. We know what you're thinking, the vacuum is sucking the water into the vase right? You have the right idea, but scientists try to avoid using the term "suck" when describing a vacuum. Instead, they explain it as gases exerting pressure from an area of high pressure to an area of low pressure. A common misconception regarding this experiment is that the consumption of the oxygen inside of the bottle is also a factor in the water rising. Truth is, there is a possibility that there would be a small rise in the water from the flame burning up oxygen, but it is extremely minor compared to the expansion and contraction of the gases within the bottle. Simply put, the water would rise at a steady rate if the oxygen being consumed were the main contributing factor (rather than experiencing the rapid rise when the flame is extinguished). (1)

The page from Harvard goes into more detail on the argument versus the error for the incorrect statement.

Argument : Oxygen is replaced by Carbon dioxide. So, there is the same amount of gas added than taken away. Therefore, heat alone most be responsible for the water level change. Source of the Error : A simplified and wrong chemical equation is used, which does not take into account the quantitative changes. The chemical equation has to be balanced correctly. It is not true that each oxygen molecule is replaced by one carbon dioxide molecule during the burning process; two oxygen molecules result in one carbon dioxide molecule and two water molecules (which condense). Remember oxygen is present in the air as a diatomic molecule. [A reader clarifies the water condensation in an email to me as follows: If the experiment were done with the sealing fluid able to support a temperature greater than 212 F and the whole system held above this temperature then the water product of combustion would remain gaseous and the pressure within the vessel would increase as a result of three gaseous molecules for every two prior to combustion and the sealing fluid would be pushed out.] Argument : Carbon dioxide is absorbed by the water. Thats why the oxygen depletion has an effect. Source of the Error : This idea is triggered from the fact that water can be carbonized or that the oceans absorb much of the carbon dioxide in the air. But carbon dioxide is not absorbed so fast by water. The air would have to go through the water and pressure would need to be applied so that the carbon dioxide is absorbed during the short time span of the experiment. Argument : The experiment can be explained by physics alone. During the heating stage, air escapes. Afterwards, the air volume decreases and pulls the water up. Source of the Error : the argument could work, if indeed the heating of the air would produce enough pressure that some air could leave. In that case, some air would be lost through the water. But one can observe that the water level stays up even if everything has gone back to normal temperature (say 10 minutes). No bubbles can be seen. Argument : It can not be that the oxygen depletion is responsible for the water raising, because the water does not rise immediately. The water rises only after the candle dims. If gas would be going away, this would lead to a steady rise of the water level, not the rapid rise at the end, when the candle goes out. Source of the Error : It is not "only" the oxygen depletion which matters. There are two effects which matter: the chemical process of the burning as well as a physical process from the temperature change. These effects cancel each other initially. Since these effect hide each other partially, they are more difficult to detect. (2)

It clearly has more to do with the temperature differences than any conversion of gases. Especially considering that a volume of oxygen and carbon dioxide will be nearly identical to human eye observation.

• 4 $\begingroup$ I'd trust Harvard (second footnote I am guessing). $\endgroup$ –  Skava Commented Jan 4, 2012 at 3:11
• 2 $\begingroup$ Yes "Skava", now go to bed! $\endgroup$ –  Larian LeQuella Commented Jan 4, 2012 at 3:12
• 3 $\begingroup$ This answer is useful in pointing the best explanation I've seen (the second link), but the text is plainly copied other pages (should be formatted as quotes) and does not make clear the general summary/conclusion. $\endgroup$ –  leonbloy Commented Jan 4, 2012 at 13:49
• $\begingroup$ I'd question one thing from that answer, though: Nowhere is a vacuum created. There's always air in the glass, and it always fills the whole space not occupied by water. When the air cools down, it doesn't contract by itself, only its pressure goes down (intuitively: Since the molecules get slower, they hammer less onto the water surface). As result the water is pressed more in by the air outside than out by the air inside, and thus flows inside. This rising water compresses the air inside, which causes air density and thus pressure inside to rise again until equilibrium is reached. $\endgroup$ –  celtschk Commented Jan 18, 2012 at 5:47
• 1 $\begingroup$ The second quotation seems to contradict the first one: first says "you might see some bubbles", the second one: "No bubbles can be seen". $\endgroup$ –  Ruslan Commented Jul 4, 2018 at 9:25

I have not actually tried this experiment, but I will make at least a few observations:

Hypothesis 1: The burning of oxygen is responsible for the reduced air pressure.

Prediction - if the burning of oxygen is the sole cause of the change in pressure, we should expect to see the water in the glass rise at a more or less constant rate from the moment the environment is sealed until the burning stops. After the candle extinguishes, there should be no more change in water level.

Hypothesis 2: The reduction in temperature after the candle extinguishes is responsible for the reduced air pressure.

Prediction - if the temperature change is the sole cause of the change in pressure, we should expect to see no change in water level while the candle is burning (in the limit that the glass was lowered very slowly). After the burning stops, the water should rise at a rate related to the temperature drop and eventually stop as the experimental setup comes to room temperature.

In order to test which explaination is correct, you should be able to merely perform the experiment and match the observation with the prediction. Of course, in real life it may be a combination of these two factors or perhaps include other reasons not listed here.

Additional measures such as putting an oxygen indicator in the glass (say a fresh slice of apple) or a thermometer would provide further insight.

• 1 $\begingroup$ As oxygen is burned - how many moles of CO2 do you get for each mole of O2 used? $\endgroup$ –  Martin Beckett Commented Jan 3, 2012 at 23:15
• 1 $\begingroup$ @MartinBeckett: Not to mention it's mostly carbon monoxide because it's imperfect burning. $\endgroup$ –  Mike Dunlavey Commented Jan 4, 2012 at 3:15
• 1 $\begingroup$ @MartinBeckett: The pertinent equation seems to be something like $C_{25} H_{52} + 38 O_2 => 25 C O_2 + 26 H_2 O$. So for 1 mole of oxygen we have 0.65 moles of $C O_2$ - a moderate reduction, and this assuming water condenses. $\endgroup$ –  leonbloy Commented Jan 4, 2012 at 14:40
• 1 $\begingroup$ @leonbloy - although with a smoky candle you do get a lot of CO. Plus since O2 is only 20% of air it would at most be a (1-0.65)*0.21 = 7% change in volume even with full combustion $\endgroup$ –  Martin Beckett Commented Jan 4, 2012 at 16:26
• $\begingroup$ @MartinBeckett: you are right, of course. See the Harvard link in the other answer for the complete picture. $\endgroup$ –  leonbloy Commented Jan 4, 2012 at 16:36

I will make this into an answer because the idea behind this question is used in an ancient medical metho d which was still used by practical nurses and even prescribed by old fashioned doctors when I was a child more than half a century ago in Greece. It is now used in alternative medicine practices

The air inside the cup is heated and the rim is then applied to the skin, forming an airtight seal. As the air inside the cup cools, it contracts, forming a partial vacuum and enabling the cup to suck the skin, pulling in soft tissue, and drawing blood to that area.

I think it was the invention of antibiotics which diminished rapidly its use, which was mainly for bronchitis pneumonia and similar afflictions, at least in Greece.

As far as the question goes, no liquids to confuse the issue of its being a strongly temperature dependent effect.

• $\begingroup$ Indeed, the practice is known as "cupping" and is often offered at spas and other health resorts. $\endgroup$ –  AdamRedwine Commented Jan 4, 2012 at 13:15
• $\begingroup$ +1 In spanish: "ventosa". I've seen it applied by my grandmother many years ago. $\endgroup$ –  leonbloy Commented Jan 4, 2012 at 13:37

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Rising water experiment

Follow FizzicsEd 150 Science Experiments:

You will need

• A clear glass cup that is taller than the candle
• Adult supervision

• Instruction

Using the playdough, fix the candle to the bowl so that it sits upright inside the bowl.

Pour some water into the bowl.

With the matches, light the candle.

Cover the candle with the glass cup. Watch what happens! If you want, you can add food colouring into the water to make the experiment more visible.

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What is happening?

You created an area of low pressure!

When the experiment is run you can see tiny bubbles escaping under the glass which shows that the air pressure increased inside the glass from the heated air as the candle burns. Once the candle runs out of oxygen, the candle burns out and the remaining air inside cools down. Cooling air contracts ( see liquid nitrogen on a balloon! ) which lowers the air pressure inside the glass. This created a pressure difference between the air inside the glass and the air outside the glass. This pressure difference caused the high-pressure air outside the glass to push the water down into the plate… allowing the water to be pushed upwards into the inside of the glass towards the lower-pressure air inside the glass.

Variables to test

More on variables here

• hot vs. cold water
• Two candles vs. one candle
• What happens when you use different liquids?

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6 thoughts on “ Rising water experiment ”

Hi When I was at school 30 years ago the oxygen use causing the rise was taught. Since then, it is my understanding from lots of reading, that the reasons behind the rise are related more to temperature as described nicely by Steve Spangler below.

A common misconception is that the consumption of oxygen by the flame in the container is a factor in the water rising. There may be a slight possibility that there would be a tiny rise in the water from the flame using up oxygen but it’s extremely small compared to the actual reason. Simply put, the water would rise imperceptibly at a steady rate as the oxygen were consumed. You likely saw the level rise almost all at once and pretty much after the flame went out.

At first, the flame heats the air inside the container and this hot air expands quickly. Some of the expanding air escapes from under the vase where you might have seen some bubbles. When the flame fades and goes out, the air in the container cools and cooler air contracts or takes up less space. That contraction creates a weak vacuum – or lower pressure – in the container. Where’s the higher pressure? Right! It’s outside the container pressing down on the water in the dish. The outside air pushes water into the container until the pressure is equalized inside and outside the container. The water stops rising when that pressure equalization is reached. https://www.stevespanglerscience.com/lab/experiments/why-does-the-water-rise/

Hi Angela, You’re right and great spot! It looks like this explanation missed the other half of the answer and it’s been updated now. Thanks for the heads up!

Thanks a lot !!! You saved me …? Tmrw was my science test and I was desparatly searching for this answer …

Great experiment to try i tried it and it failed ):

Oh no! How did you set your experiment up? Usually, the failure happens when the water on plate isn’t high enough. Give it a go again!

Yeah I will(:

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The burning candle - rising water experiment

This is a classic experiment. On a plate with a little water place a candle and light it. Place a drinking glass over it. The light goes out while sucking up the water.

At least two things happen:

• The oxygen O₂ is changed to CO₂
• The air is heated up a few degrees
• Water is sucked up

But then I tried to change the experiment with a vase (big glass) and opening upwards and place the candle at the bottom. Then lit the candle and place plastic over the opening. The result was that the light went out but it didn't suck down the plastic. So it there is no vacuum in the glass? A strange thing is that the plastic was pulsing like it was breathing. It can be seen here in my video https://youtu.be/aolz8Y27Lsk

Why is the experiment so different from the other?

• experimental-chemistry

• $\begingroup$ Obviously the plastic didn't completely seal the vase. $\endgroup$ –  MaxW Commented Mar 19, 2020 at 19:10
• $\begingroup$ Your chemical description is incomplete. $\endgroup$ –  Karl Commented Mar 19, 2020 at 19:41
• $\begingroup$ There must be a leak somewhere, because the gas volume does not change during the combustion. And the volume must change during the combustion. It must increase or decrease, as explained by Karsten Theis $\endgroup$ –  Maurice Commented Mar 19, 2020 at 19:54
• $\begingroup$ The seal on your vessel has to be perfect for this to work. An inverted glass vessel achieves this; it is very, very unlikely that a plastic seal will do so. $\endgroup$ –  matt_black Commented Mar 20, 2020 at 10:49

2 Answers 2

Changes in volume

The chemical reaction for burning a candle is something like this:

$$\ce{C25H52 + 38 O2(g) -> 25 CO2(g) + 26 H2O(g)}$$

For every 38 dioxygen molecules used, you are making 25 carbon dioxide molecules and 26 water molecules (which start out as a gas, but will condense once they reach an area of lower temperature such as the glass surface). So once the flame is out and the water has condensed, the volume should be less than that of the fresh air (20 % of the volume initially are oxygen. Its volume will be replaced by that of carbon dioxide, so the volume will go from 100% to 25/38 * 20% + 80% = 93%). While the candle is burning, however, the temperature is higher, and some of the water will be in the gas phase. Also, while the air was already hotter than room temperature before the container was covered, the temperature will rise as soon as the influx of cooler (fresh) air is cut off.

How hot will it get?

A tea light produces heat at about 30 J/s, and (with a molar heat of combustion of about 15,000 kJ / mol) used up $\pu{80 \mu mol}$ oxygen per second. This means you need about 10 mL of fresh air each second the candle burns. The container has a volume of about 400 mL, so the candle should burn <40 seconds. In the video, it burned about 2 minutes (not bad for an estimate). Using up all the oxygen in the container would give off about 1.2 kJ, which is sufficient to raise the temperature by 1000 degrees Celsius if it were isolated. As it is, most of the heat flows into the container.

What is different when using water?

Water has a higher heat capacity, so it is more efficient in cooling down the gas (and the container). As a consequence, the water level will rise appreciably. As MaxW mentions in the comments, the plastic probably did not seal perfectly. The pulsing could be intermittent flow of gas, or temperature fluctuations because of mixing.

• 1 $\begingroup$ So in the next experiment I will 1) put water at the bottom to increase coolant 2) light the candle and cover immediately 3) use more heat resistant plastic 4) use better and more rubber bands. Goal: To see the plastic cover be sucked in the container (will that happen?) (Sorry for making such a lousy experiment) $\endgroup$ –  hschou Commented Mar 19, 2020 at 22:06
• 1 $\begingroup$ @hschou Instead of a candle, you could use some steel wool soaked in vinegar. It will use up the oxygen without making carbon dioxide (the oxygen ends up being rust). This experiment removes two complications - the carbon dioxide and the large changes in temperature. But I encourage you to try your 2nd experimental design as well - the first try is always lousy, and you only learn by repeating experiments. $\endgroup$ –  Karsten ♦ Commented Mar 20, 2020 at 0:17

Why do most people want to believe that on burning fuel little or no carbon monoxide is created?

Yes, it could be true, mainly CO2 is formed, but read these qualifying comments from a source :

A properly designed, adjusted, and maintained gas flame produces only small amounts of carbon monoxide, with 400 parts per million (ppm) being the maximum allowed in flue products.

And, per the same source:

Incomplete combustion occurs because of: Insufficient mixing of air and fuel. Insufficient air supply to the flame. Insufficient time to burn. Cooling of the flame temperature before combustion is complete.

Also, per Wikipedia , to quote:

In the presence of oxygen, including atmospheric concentrations, carbon monoxide burns with a blue flame, producing carbon dioxide.[10]

So, many combustion reactions perhaps should be expressed in steps including:

$\ce{2 CO + O2 -> 2 CO2}$

So, perhaps more likely, the presence of CO is more of a reality than many would want to believe.

In the case of your experiment, leakage (from possible thermal exposure damage and/or a poor seal) along with incomplete combustion may be some route causes (as carbon monoxide is not very soluble in water, 27.6 mg/L as compared to CO2 with 1,450 mg/L at 25 °C).

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24 Shockingly Fun Electricity Experiments and Activities for Kids

Play dough circuits, LED magic wands, and more!

Electricity is all around us, so we tend to take it for granted. It’s a fascinating subject for kids, though, so they’ll love these electricity experiments and activities. You may need to invest in a few simple supplies for some of these activities, but you’ll be able to reuse them for multiple activities year after year. The hands-on experience kids will get makes the extra effort worthwhile.

1. Start with an anchor chart

Static electricity is most kids’ intro to this concept, and it leads nicely into electrical energy and circuitry. These colorful anchor charts help you teach both.

Get tutorial: Anchor chart about electricity and electricity anchor chart

2. Bend water with static electricity

Most static electricity experiments are quick and easy enough for anyone to try at home. This is a great example: Charge a comb by rubbing it against your head, then use it to “bend” a stream of water from a faucet.

Get tutorial: Water balloon experiment

3. Separate salt and pepper using a magic spoon

This static electricity experiment works because pepper is lighter than salt, which makes it quicker to jump to the electrically charged plastic spoon. So cool!

Get tutorial: Salt and pepper experiment

4. Move a bubble using a balloon

Balloons are a fun way to teach about static electricity. Combine them with bubbles for a hands-on activity students will really love.

Get tutorial: Bubble experiment

5. Flap a (paper) butterfly’s wings

Speaking of balloons, try using them to help a butterfly flap its tissue paper wings. Little ones’ faces light up when they see the butterfly come to life.

Get tutorial: Butterfly wing experiment

6. Make jumping goop with static electricity

Kick your static electricity experiments up a notch by mixing a batch of cornstarch “goop,” then making it “jump” toward a balloon. Amazing!

Get tutorial: Jumping goop experiment

7. Assemble circuits from play dough

When you’re ready to explore electrical energy, start with play dough circuits. You’ll need a battery box and mini LED lights. Mix up your own batches of insulating and conducting play dough using the info at the link.

Get tutorial: Play dough circuit experiment

Buy it: Battery box and clear LED lights at Amazon

8. Create a classic potato clock

A potato clock is an impressive way to kick off or end a unit on electricity. Your students will never look at potatoes the same way again.

Buy it: Potato Clock experiment kit

9. Find out if water conducts electricity

We’re always telling kids to get out of the water at the first sign of a lightning storm, so use this demo to help them understand why. You’ll need alligator clip wires, mini LED bulbs, and button cell batteries.

Get tutorial: Water electricity experiment

Buy it: Alligator clip wires , mini LED bulbs , and button cell batteries at Amazon

10. Whip up wizard wands

Lumos! If your kids are fascinated by Harry Potter and the world of magic, they’ll love this electricity project that turns ordinary sticks into light-up wands! Learn how it’s done at the link.

Get tutorial: Wizard wand project

11. Play a DIY steady-hand game

Electricity experiments like this one are perfect for exploring the idea of open and closed circuits. Plus, kids will have so much fun playing with them.

Get tutorial: Steady-hand game

12. Copper-plate coins using electricity

We all know electricity lights up a room and powers phones, computers, and even cars. But what else can it do? This electroplating experiment is a real jaw-dropper. 

Get tutorial: Copper plate coins experiment

13. Create an index card flashlight

This DIY flashlight really turns on and off! It only takes index cards, aluminum foil, mini LED bulbs, an button cell batteries.

Get tutorial: Index card flashlight

Buy it: Mini LED bulbs and button cell batteries at Amazon

14. Twirl some homopolar dancers

These sweet little twirling dancers are a fantastic demonstration of a homopolar motor. In addition to basic AA batteries, you’ll need neodymium magnets and copper wire.

Get tutorial: Homopolar dancers

Buy it: Neodymium magnets and copper wire at Amazon

15. Build multiple circuits

Create more than one circuit using play dough to create a series. The positive leg of the LED is near the battery terminal. Since the battery can only push the electricity one way, you can create a circuit of two or more to create a larger circuit.

Get tutorial: Series circuit experiment

16. Make a coin battery

Use a stack of coins (the more coins you use, the more electricity produced) to make a battery.

Get tutorial: Coin battery

17. Make an electromagnet

Make an electromagnet, or a magnet that uses an electric field, by wrapping wire around an iron nail and running current through the wire. An electric field is created around the nail and, sometimes, the nail will stay magnetized even when the coil is removed.

Get tutorial: Electromagnet project

18. Create a pencil resister

Learn about how resisters control the amount of electricity that flows through a circuit. Use pencils (a great way to use those old stubby pencils that are sharpened at both ends) as part of the circuit, and watch the brightness of the build change when the resistance in the circuit changes.

Get tutorial: Pencil resister project

Buy it: AA batteries , battery holder , LED light bulbs , and alligator clips at Amazon

19. Find out what conducts electricity

Figure out what objects are made of material that conducts or does not conduct electricity. Collect common objects such as a key, chalk, wood, and/or candle. Then, test each object by putting it between a battery and a light bulb and touching foil to the base of the bulb. If the bulb lights up, the object conducts electricity!

Get tutorial: What conducts electricity? experiment

Buy it: AA batteries and LED light bulbs at Amazon

20. Create electric paint

Use electric paint to create a circuit and light up a painting with batteries and LEDs. You will need a multimeter for this project (here’s how to use a multimeter ).

Get tutorial: Electric paint project

Buy it: Multimeter , electric paint , 9-volt batteries , LED light bulbs , and alligator clips at Amazon

21. Create an electromagnetic train

Show the connection between electricity and magnetism by creating a train with a battery and some neodymium magnets. One note: This is a project for older students who have close adult supervision, as neodymium magnets are very strong.

Get tutorial: Electromagnetic train project

Buy it: Neodymium magnets at Amazon

22. Create an electroscope with a soda can

An electroscope detects the presence of an electronic charge. Create a basic but effective electroscope with a soda can, insulation tape, aluminum foil, and a Styrofoam cup. Put it near various surfaces and see what happens.

Get tutorial: Soda Can Electroscope

23. Turn dirt into a battery

Electricity can even conduct in dirt. Create a dirt battery with galvanized steel screws (very important), an ice cube tray, copper wires, and soil. Make it more interesting by putting lemon juice or vinegar in the dirt.

Get tutorial: Dirt Battery Experiment

Buy it: Copper wire and galvanized screws at Amazon

24. Lemon battery

Use a lemon to create a battery with coins and a multimeter. It’s a great way to show students how literally anything can be a conductor of electricity.

Get tutorial: A Simple Lemon Battery

Buy it: Multimeter at Amazon

Love these electricity experiments and activities? Check out Easy Science Experiments Using Materials You Already Have On Hand .

Plus check out turn muggles into wizards with harry potter science experiments ..

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72 Easy Science Experiments Using Materials You Already Have On Hand

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