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Learn about Hot and Cold Temperature: Easy Science Experiments for Kids

Teach kids about temperature as they perform easy science experiments with hot and cold water and the our free printable.Thank you for visiting. This post…

Teach kids about temperature as they perform easy science experiments with hot and cold water and the our free printable.

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We did 6 different science activities to learn about temperature and the difference between hot and cold. We have a free printable activity to go along with all the hands-on activities so your little scientists can have fun understanding temperature while learning more about the world around them. Each of the activities are super simple to set up, mainly because most of the supplies come straight from your kitchen faucet.

I loved watching my kids try out these science experiments. They were so eager to check everything out and best of all their understanding of temperature grew. I think that my favorite activity was watching the food coloring disperse in hot and cold water–such a simple activity and yet so pretty to watch! If you enjoy watching your kids do science as much as I do, check out this free homeschool science curriculum .

Hot & Cold Science Experiments: 6 different science activities for kids to learn about temperature and the difference between hot and cold including a free printable to go along with all the hands on activities. (#science)

More Science Experiments:

Grow a Rainbow Science Experiment
Snowflake Symmetry Activity
How to Make Crystal Balls

Learn about Hot and Cold Temperature Science Experiments

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Voss Water bottle (or plastic bottle)
Red and blue food coloring
Thermometer (We used a candy thermometer)
Water balloons
Ice Cube tray
Glass measuring cups

VOSS Artesian Water (Still), 500 ml Plastic Bottles (Pack of 24)

DIRECTIONS:

Frozen Water

Fill containers half full with water. Mark the water line with a marker or I used a rubber band because we use our water bottles a lot. Put them in the freezer until they are completely frozen. Have children look at the new water lever (ice level). The frozen line should be above the water line because when water freezes it expands because the hydrogen bonds in the water that form are more spread out then when it is in liquid state.

Red and Blue Food Coloring Race

Fill one tall container with ice cold water and another tall container with hot water (not boiling). Have child drop a few drops of red food coloring in the hot bottle and blue food coloring in the cold water and watch (this experiment is very fast so don’t look away). Technically you could use whatever color food coloring you have but since red and blue help to reinforce the difference in temperatures we used those colors. The blue food coloring should move slower through the water compared to the red food coloring because the water molecules in the hot water have more energy and move faster then the water molecules in the cold water.

Blue Ice Melt

Fill a pitcher with water and add drops of blue food coloring. Fill an ice tray with the blue water and put it in the freezer until the ice is solid. Fill a container with room temperature water and place the blue ice inside. The ice should float and the blue water that melts from the ice cube should sink. This is because cold water (and air) is more dense compared to regular temperature water and will sink in warmer water. They may have heard before that hot air rises and cold air sinks, now they can visualize it.

Hot & Cold Balloons

Fill small balloons with some air. We used water balloons. Make them relatively the same size. Place one in cold water and one in hot water. We used a pink balloon for the hot water and the blue balloon for the cold water. The hot water balloon should get larger as the air expands as it gets warm and the cold water balloon should shrink as the air inside condenses.

Thermometer Reading

After the balloon test we used our thermometer to measure the water temperatures and then we wrote the temperature on our Hot and Cold Molucule Craft (See below).

Hot and Cold Molecule Craft (Available to download for free below)

Have children glue molecules in the hot and cold cups showing their understanding of hot and cold. The hot molecules should be spread out and moving around while the cold molecules should be condensed and slow moving.

DOWNLOAD THE PRINTABLE HERE:

Print the directions here:.

Hot and Cold Temperature Science Experiments

Thermometer

Instructions

Frozen Water Fill containers half full with water. Mark the water line with a marker or I used a rubber band because we use our water bottles a lot. Put them in the freezer until they are completely frozen. Have children look at the new water lever (ice level). The frozen line should be above the water line because when water freezes it expands because the hydrogen bonds in the water that form are more spread out then when it is in liquid state. Red and Blue Food Coloring Race Fill one tall container with ice cold water and another tall container with hot water (not boiling). Have child drop a few drops of red food coloring in the hot bottle and blue food coloring in the cold water and watch (this experiment is very fast so don't look away). Technically you could use whatever color food coloring you have but since red and blue help to reinforce the difference in temperatures we used those colors. The blue food coloring should move slower through the water compared to the red food coloring because the water molecules in the hot water have more energy and move faster then the water molecules in the cold water. Blue Ice Melt Fill a pitcher with water and add drops of blue food coloring. Fill an ice tray with the blue water and put it in the freezer until the ice is solid. Fill a container with room temperature water and place the blue ice inside. The ice should float and the blue water that melts from the ice cube should sink. This is because cold water (and air) is more dense compared to regular temperature water and will sink in warmer water. They may have heard before that hot air rises and cold air sinks, now they can visualize it. Hot & Cold Balloons Fill small balloons with some air. We used water balloons. Make them relatively the same size. Place one in cold water and one in hot water. We used a pink balloon for the hot water and the blue balloon for the cold water. The hot water balloon should get larger as the air expands as it gets warm and the cold water balloon should shrink as the air inside condenses. Thermometer Reading After the balloon test we used our thermometer to measure the water temperatures and then we wrote the temperature on our Hot and Cold Molucule Craft Hot and Cold Molecule Craft Have children glue molecules in the hot and cold cups showing their understanding of hot and cold. The hot molecules should be spread out and moving around while the cold molecules should be condensed and slow moving. We used marshmallows. Available here: https://alittlepinchofperfect.com/learn-hot-cold-temperature-science-experiments-kids/

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Hot and Cold Water Density Experiment

July 20, 2022 By Emma Vanstone Leave a Comment

This easy science activity demonstrates the difference in density between hot and cold water. It can be a bit messy so I would either do it outside or put the jars in a tray.

The demonstration works as cold water is more dense than hot water so the hot water sits on top of the cold.

When water is heated, water molecules move around faster, bounce off each other and move further apart. As there’s more space between the water molecules the density of warmer water is less than the same volume of cooler water.

blue cold water sitting under red warmer water for a science experiment about density

You’ll need

Two small or medium glass jars

Small sheet of card

Food colouring

Tray – optional but advised

How to make hot and cold water density jars

Fill one of the jars with hot water and add a couple of drops of red food colouring.

Fill the second jar with cold water and add a drop of blue food colouring.

Check both jars are as full as possible.

Hot water on top of cold

Place a sheet of card over the jar filled with hot water and carefully place it on top of the jar with the cold water.

When the jars are balanced, carefully remove the card.

The two colours of water should remain separate.

Cold water on top of hot

Refill the jars and try again. This time place the cold water on top of the hot water.

The two colours of water should mix.

Density of water

Warm water is less dense than cold water so the red warm water sits on top of the cold water when the card is removed from between the jars.

If you put the hot water on the bottom the colours mix as the denser cold water drops down into the less dense hot water.

Our photo isn’t perfect as it’s hard to remove the card between the jars without some water spilling out, but do send me a photo if you get a better result.

Another density demonstration can be done using salt to increase the density of one jar of water. In the image below the blue water has the salt added.

Two glasses on top of each other filled with water, food colouring and different amount of salt. One colour floats on top of the other.

Safety Notice

Science Sparks ( Wild Sparks Enterprises Ltd ) are not liable for the actions of activity of any person who uses the information in this resource or in any of the suggested further resources. Science Sparks assume no liability with regard to injuries or damage to property that may occur as a result of using the information and carrying out the practical activities contained in this resource or in any of the suggested further resources.

These activities are designed to be carried out by children working with a parent, guardian or other appropriate adult. The adult involved is fully responsible for ensuring that the activities are carried out safely.

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Hot and Cold Water Density - Teach Kids How Temperature Effects Water Density

Posted by Admin / in Matter Experiments

An experiment to teach kids about the difference in density between hot and cold water and the natural flow of warmer or cooler water.

Materials Needed

Two clear cups of equal size
Index card or wax paper
Food coloring (2 colors-blue and red)
Casserole pan

EXPERIMENT STEPS Have an adult help with this experiment since hot water will need to be handled.

Step 1. Place a full cup of water in the freezer or refrigerator and allow it to cool for 15 minutes.

Step 2. Remove the water from the freezer and mix with a few drops of blue food coloring.

Step 3. Heat up a full cup of water. Have an adult help heat the water either in a microwave oven or on the stove. Hot tap water will work it if is very hot. Handle the hot water very carefully.

Step 4. Mix the hot water with a few drops of red food coloring.

Step 5. Place the cold (blue) water cup in the bottom of the casserole pan.

Step 6. Carefully hold the index card on top of the hot (red) water and flip it upside down, resting the cup on top of the cold (blue) water cup. If the cup opening size is larger than an index card, a piece of wax paper will also work for this step, however, if the wax paper stays in contact with hot water too long it will quickly start to stick to the cup.

Step 7. Quickly remove the index card allowing the cold water and hot water to mix. Observe what happens to the different temperature water.

SCIENCE LEARNED

Different temperature water has different density. The normal density of water is 62.4 pounds per cubic foot. Warmer water is less dense and will have a lower weight per cubic foot of space. Colder water is more dense and will weight more for each cubic foot of space. When the index card is removed between the hot and cold water, nothing really happens. The hot water stays elevated above the colder (blue) water. The cold water is more dense than the hot water. The red and blue coloring will stay separated until the water temperatures start to even out. This will actually take quite a while if the very hot and reasonably cold water is used for the experiment. The experiment cannot really be performed with the hot water starting on the bottom. The hot water will rise, but in the process the red food coloring will mix with the blue food coloring in the cold water and result in purple water.

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Liquid Density Experiment

in Matter Experiments

Experiment with the density of different types of liquids.

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Hot and Cold Water Density Experiment

What happens when hot and cold water meet? This easy and colorful hot and cold water science experiment reveals how temperature affects the density of water, giving kids a fun way to see science in action!

In this experiment, we explore the concept of density by comparing how hot and cold water behave when mixed.

Density measures how tightly packed molecules are in a substance. Observe how the density of water changes with temperature, using vibrant colors! Let’s explore how cold water molecules and hot water molecules interact in this fun science experiment .

Grade Level Recommendation : 3rd Grade and above.

💡Find printable instructions and an observation sheet for this experiment in the CLUB .

2 clear glass jars or cups (baby food jars work well)
Food coloring (red and blue work best)
Warm (not boiling)
2 index cards or pieces of stiff paper

Hot vs Cold Water Mixing Instructions

Ask: Is cold water denser than hot water? (leading to cold water sinking and hot water rising)

Prepare the Water : Fill one jar with cold water and add a few drops of blue food coloring. Fill the second jar with warm water and add a few drops of red food coloring.

💡 For this science experiment, it’s important to have the same volume or cold water and the same volume of hot water. Learn more about variables here .

Invert the Hot Water Jar : Place an index card on top of the hot water jar, ensuring it’s tightly sealed with no gaps.

Stack the Jars : Carefully invert the hot water jar and place it on top of the cold water jar.

Remove the Card : Slowly pull out the index card so the jars are directly connected.

Hot and Cold Water Density Experiment Explanation

In this experiment you would have noticed that the red hot water stays on top of the cold blue water because hot water is less dense than cold water. When reversed (cold water on top), the colors mix quickly to make purple water as the denser cold water sinks. This is because hot water rises and cold water sinks!

Density is a property that explains how tightly molecules are packed in a substance. In cold water, the water molecules are closer together, making them denser. When water is heated, the water molecules move apart and bounce around, decreasing their density. There are fewer molecules in hot water and it weighs a bit less than the same volume of cold water.

In this experiment, the warmer (less dense) water stays on top of the colder (denser) water. However, the denser cold water sinks if you put cold water on top of hot water, causing the two to mix rapidly. This experiment demonstrates how the temperature of a substance can affect its movement and interactions.

This is also why ocean currents and weather patterns occur—cold, dense water sinks while warmer water rises!

💡 Try our Ocean Current Activity to demonstrate this.

Extension Activities:

Temperature in Nature : Research how temperature changes from day to night.
Salt and Water Density : Add salt to the cold water to see if it becomes denser.
States of Matter: Explore experiments that involve matter and its properties, including how changes in temperature affect substances.

Related Experiments To Explore Density

Here are some fun density experiments :

Oil and Water Science : Try activities that show how oil and water don’t mix because of their different densities.
Lava Lamp Science Experiment : Discover how density and temperature changes cause bubbles to rise and fall, just like a lava lamp!
Liquid Density Tower: Layer or mix different liquids to observe how liquids with different densities either float or sink.

Helpful Science Resources

Here are a few resources that will help you introduce science more effectively to your kids or students and feel confident presenting materials. You’ll find helpful free printables throughout.

Best Science Practices (as it relates to the scientific method)
Science Vocabulary
All About Scientists
Free Science Worksheets
DIY Science Kits
Science Tools for Kids
Scientific Method for Kids
Citizen Science Guide
Join us in the Club
Printable Science Project Pack 👇

Subscribe to receive a free 5-Day STEM Challenge Guide

~ projects to try now ~.

Balloon In Hot and Cold Water – Experiment

March 30, 2021
7-9 Year Olds , Household Items , Physics

Let’s discuss about ‘Balloon in hot and cold water experiment’ in this article. This interesting balloon experiment helps children to learn about density , surface tension , and air pressure .

Balloon in hot and cold water experiment

The volume of air changes based on the temperature surrounding it.
Air expands or contracts based on increase or decrease in surrounding temperature.

Things you need to do Balloon Experiment

1) Two plastic/ glass container (bottles)

2) Balloons

3) Hot Water

4) Ice cubes as a cold water source

5) Containers to place hot and cold water

Material Required For Balloon In Hot And Cold water Experiment

Preparation Steps

1) You can prepare your children or students by asking “How can you inflate the Balloon without touching it?”.

2) Note down their expected answers. But discuss their solutions only after performing the experiment to catch the science concepts behind it easily.

Step by Step Directions

Let’s start with the hot air experiment.

Step-1:

Take a glass container and add cold water. Then, add few ice cubes to it to keep it cold.

Step-2:

Pick another glass container and add some amount of hot water into it. Ensure the hot water’s hotness need not to be sizzling.

As step 3, bring our Balloon over the neck or mouth of the crystal clear plastic bottle in an upside-down position. And fix the mouth of the Balloon to the mouth of the bottle as shown in the picture.

Make sure the bottle is empty before you attach the Balloon to it.

Repeat the same method and prepare another set of water bottle and Balloon using the other empty bottle.

In this step, keep the ballon attached bottle inside the container, which consists of hot water. Let the bottle sit in hot water for some time.

Keep The Bottle With Balloon In Hot And Cold Water

You will observe the Balloon starts inflating itself without any external force. Amazing, isn’t it!?

Step-5:

And then bring the same and another set of water bottle into the container which consists of cold water. And allow it to sit for some time to see the results.

You will observe the Balloon starts shrinking itself by deflating the air inside it.

Note: If you feel the hot water is becoming cool, replace it with another hot water cup. In the same way, if you feel the cold water is becoming hot due to outside temperature impact, add some more ice cubes and make it cool. In this way, you can maintain the temperatures of the water while repeating the experiments.

Balloon In Hot And Cold Water Experiment

Science Behind Expanding Balloon on Hot Water

The quantity of air occupied in a particular space, i.e., an open or closed container, denotes ‘Volume.’

Well, an empty water bottle is also populated with a certain amount of air molecules inside it—the air molecules inside and outside the bottle move with equal pressures at normal surrounding conditions.

In this activity, when we attach a balloon over the bottle’s mouth and place it in a hot water container, the Balloon starts inflating. It is because the hot air molecules enter into the Balloon from the bottle, which is in a hot water container.

These hot air molecules move faster inside the Balloon and occupy more space as they become less dense than usual. When they become less dense, it requires more space to settle, and that is why the Balloon starts inflating to provide more space for hot air molecules.

And when the Balloon inflates in hot water, bring it into the container containing cold water. Here, the cold air molecules replace the hot air molecules because hot air molecules cool down due to cold water.

When the air molecules become colder, air molecules’ density gets back to a denser state and requires less space to occupy. That is why the inflated Balloon deflates when the bottle is placed inside a cold water container.

This is how the volume of air calculated:

Volume= Mass x Density

Balloon in Hot And Cold Water Science Experiment

Safety Tips

Have adult supervision at all times during the experiment to avoid any unforeseen incidents.

Suggested to wear gloves and safety glasses while doing experiments with hot water.

Avoid handling hot water by small kids.

Learning for Elementary, Middle School, and High School Students

The same experiment can be used differently based on the level /grade of the students.

Elementary Students

When kids are in elementary school, it is the best time to learn about different states of matter, i.e., solids, liquids, and gases. Solids and liquids are visible to the naked eye, and hence students can easily catch up with the properties and characteristics. And it is easy for them to compare various objects and liquid things and determine the state of matter properties.

But when coming to gases, it is difficult for them to determine their properties because gases won’t appear to the naked eye, and children go confused. That is why we need to explain them clearly by concentrating much on performing various science experiments that involve gases. One such experiment is the ‘Balloon in a bottle’ experiment.

Through this experiment, students can quickly learn about gases and their properties.

Middle School Students

In middle school, students focus on macroscopic particles and determine the objects around them and tell whether they have solid or liquid or gaseous properties. Because at this level, they will get to learn about states of matter in regards to their arrangement, position, and movement. Also, they can explore that all forms of matter are made of atoms and molecules that consist of weight, especially gases. As the air is invisible, they think that gases do not have mass, but they learn about gases containing mass with this experiment.

Besides, they can explain the conservation of matter with a good reason using the concept of closed systems.

High School Students

At this level, as the name suggests, students become sharp and can apply their knowledge on gases. This knowledge helps in understanding even the difficult context of gases, i.e., ‘Gas Laws.’ Also, they can apply Charles Law and explain Gas Law. And using conservation of matter principles and laws, they will make out the differences in temperatures and their relation to the volume of gas.

In this way, students at different school grades learn the gaseous properties by performing this super classic experiment of ‘Balloon in a Bottle.’

Laws Behind the Experiment

Gas Law or Gas Laws is/are a collection of laws which include Boyle’s Law, Charles’s Law, Gay-Lussac’s Law, Ideal Gas Law, and Avogadro’s Law. These laws combine to state how an amount of gas reacts to changes in temperature, pressure, and temperature. The following are such statements these combined laws work on:

1) The complete temperature of a gas

2) The amount of volume working with a gas

3) The amount of pressure experienced between the walls of a container and a gas

4) The mass of a gas

The above-mentioned combination laws were a great invention during the 18th century, and here are the definitions of each law:

Boyle’s Law: The law which states the kith and kin between the volume and pressure of a given amount of gas is nothing but Boyle’s Law.

Charles’s Law: Charles’s Law is the law that tells about the absolute temperature of a gas and its association with the volume employed by it.

Avogadro’s Law: The type of law which states the correlation between the number of moles of a gas and the amount of volume occupied by it refers to Avogadro’s Law.

Gay-Lussac’s Law: Gay-Lussac’s Law tells that the relation between the absolute temperature and its pressure is directly proportional at constant volume.

Ideal Gas Law: Ideal gas law is a combination of three laws, i.e., Boyle’s Law, Charles’s Law, Avogadro’s Law, and hence refers to the term ‘combined gas law.’ This law states the differential behavior of gases at different conditions and concludes that a gas’s pressure is directly proportional to the absolute temperature.

Pressure, volume, and temperature are the three significant physical factors that determine the behavior of gases. When these parameters are at standard conditions, the activities of all types of gases remain the same. The states of gases can vary based on the condition.

So, the gas law and all other five laws state all gases’ behavior is associating with all three physical parameters.

Boyle’s Law Formula: P∝1/V

Charles’s Law Formula: V∝T

Avogadro’s Law Formula: V ∝ n

Ideal Gas Law Formula: PV= nRT

Gay-Lussac’s Law Formula: P ∝ T

Here, P= Pressure of the gas, V= Volume of the gas, T= Absolute Temperature of a gas, n= Number of moles, R= Equilibrium Constant.

Here are some worksheets that would complement the science experiment. Attempting these worksheets might help studnets to sustain the knowledge gained through the experiment. On the other hand, teachers use these worksheets to understand and monitor student’s previous and current knowledge.

https://scied.ucar.edu/sites/default/files/files/activity_files/BalloonOnBottle_0.pdf

https://www.flinnsci.com/api/library/Download/e2dfff9fc2324f51889429583a51ac63

https://ps21pd.weebly.com/uploads/1/2/0/6/12065719/kinetic_theory_-_hot_and_cold_balloons.pdf

https://www.sciencenorth.ca/sites/default/files/2020/June%202%20Grade%207%20Particle%20Theory%20Offline%20ENG.pdf

Practical Applications

Let’s learn how to apply these science concepts in real life applications happening around us.

Hot air balloon: Yes, the science behind hot air balloon and Balloon in the bottle activities is similar, i.e., hot air rises, sending the cool air to replace the space created by it. When you provide heat flames in the hot air balloon set up, the heat energy enters into the Balloon.

Generally, the hot air consists of less dense air molecules, which tend to rise. That’s why and the hot air balloon rises in the sky until they provide enough heat.

Not only air, any substance that exhibits less dense molecules than the surrounding gaseous or liquid matters float . Forex: Wood floats on top of the water because wood consists of less dense molecules than water. This phenomenon of increasing the molecules’ speed regarding the increase in temperature of a gas refers to ‘Thermal Expansion.’ And the wonder of floating objects due to the pressure or force exerted is ‘Buoyancy.’

Sun Producing Wind on Earth: The winds produced by Sun on the Earth also exhibit the same phenomenon, i.e., thermal expansion and buoyancy.

Earth’s temperature is uncertain, so we cannot predict its long-term weather and climatic conditions. It is because different parts of Earth receive heat from Sunlight at different times as Earth is round and rotating.

So, the Sun can’t provide Sunlight to all parts of the Earth at the same time. Hence, Earth receives different air temperatures at places closer to the surface of the Earth. Besides, the Sun’s angle is focussing its Sunlight on the Earth also plays a significant role in changing the temperatures of Earth.

According to the above concepts, several continents on Earth receive more heat than other continents. Comparing land and water, land absorbs more heat faster than water, and therefore we see continents with more land exhibits high temperatures.

But during nights land releases heat more quickly than air and hence we feel cooler climates at night time. In this way, Earth reveals different climatic conditions and atmospheric temperatures during the day and night times.

Let us discuss these concepts in detail with a practical example, i.e., Off-shore and On-shore Winds. During nights, the oceans’ surface gets warmer so quickly because the surrounding land cools down and shows lesser temperatures.

As a result, the warmer air becomes less dense and rises upwards, leaving the space on the surface occupied by the cold air from the land. Thus, creating the off-shore winds that produce renewable and pure energy.

And at daytime, we experience on-shore winds that mean the land absorbs more heat from the Sun and exhibits warmer air. This hot air does not remain on the land surface; instead, it rises into the air because it consists of less dense air molecules.

Simultaneously, the temperature at the ocean level exhibits less heat than the land surface temperature. So, the cold air from the ocean surface replaces the hot air molecules’ space creating on-shore winds.

Lesson Plan

Here is the best lesson plan on the ‘Balloon in hot and cold water’ experiment.

Preparations

1) Ask the students whether they can inflate the Balloon without touching it. Note down their answers and discuss their solutions after the experiment.

2) First, invite your student’s answers and discuss their solutions with a scientific reason.

3) You can encourage and inspire students by telling them that they are upcoming engineers, chemists, and other respectable designations. Forex: if a student predicts the answer would be ‘by adding baking soda and vinegar,’ explain why his response went wrong. Then, encourage him by saying he/she is thinking smartly like a chemist. In this way, depending on their predictions, a teacher can inspire them with specific designations.

4) If a student does not respond to your challenge of inflating a balloon without touching it, then give him an example and ask him/her to compare. Let the student come up with his/her answer with a bit of explanation.

Guide your students on the instructions of the ‘Balloon in hot and cold water’ experiment step by step, clearly as mentioned at the top of this post. You can also ask and discuss a few questions related to the subject while experimenting. Such that students feel more encouraged and involved in the topic rather than feeling bored.

Here are the basic questions you can discuss with students:

1) Why does the Balloon inflated on itself?

2) What is the difference between hot and cold water changes and their impact on the Balloon?

3) How long the Balloon takes time to inflate itself in hot water?

Explain about Misconceptions

Students think that hot air blows up the Balloon as the hot air rises upwards. But prove it as a misconception by reversing the bottle with an inflated balloon. Still, the Balloon remains inflated without deflating. It is because hot air rises when there is cold air beside it.

Finally, explain the background science involved in this experiment and discuss students’ predicted answers with a scientific reason. Tell them clearly that their answers may not apply in this science activity, but they may use them in another way of experimenting.

In hot water, the Balloon inflated because of hot air molecules, and in cold water, the Balloon deflated because of cold air molecules. The hot air molecules are less dense in weight and tend to rise and occupy more space. That’s the reason the hot air molecules travel inside the Balloon and make it expand. In contrast, the cold air molecules are denser in weight and require less space, causing the Balloon to deflate.

Take an empty plastic water bottle. Attach a balloon (make sure it is not leaking anywhere on its surface) to the bottle’s mouth using its neck part by placing it upside down. That means the mouth of the Balloon and the bottle gets attached in opposite directions using their mouthparts. Now place the bottle set up in a container that consists of hot water in it. Leave it for some time. The Balloon starts inflating by filling its inside part with hot air molecules.

Bring the Balloon’s mouth part in an upside-down position over the neck part of the bottle. And then stretch the Balloon’s opening around the neck part of the bottle. But before that, you need to uncap the bottle. That’s it! Your Balloon’s opening nicely sits over the bottleneck part.

Boyle’s Law is valid at very high temperatures until or unless the gas remains as a gaseous matter. Because at high temperatures, the gases may change their state of mass, for which Boyle’s law is not applicable. Boyle’s law tells that the volume and pressure of a gas-related each other quite the opposite.

When you squeeze the bottle, the Balloon begins inflating itself because we squeeze some air molecules into it while squeezing the bottle. And due to more air occupying inside the Balloon, the Balloon starts expanding and inflates itself to fit the air molecules coming inside. When you stop squeezing the bottle, the balloon deflates.

When you let the Balloon warm up again, it starts inflating itself because of warmer air molecules. The warmer air molecules rise and enter into the Balloon, making it expand. Hot air molecules are less dense in weight and tend to travel upwards. And they require more space since they like to scatter in larger areas.