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Egg in a Bottle Science Experiment

Can eggs move by themselves? Maybe not, but with the help of air pressure, they can be pushed into a glass bottle without being touched!

In this experiment, your young scientists will learn about density and air pressure. And when you watch our demonstration video, you’ll see that although things didn’t go exactly as we expected, this experiment is always fun and educational. Printable instructions and a materials list are included.

JUMP TO SECTION: Instructions | Video Tutorial | How it Works

Supplies Needed

Hard-Boiled Egg (shell removed)
Glass Bottle
Thick Piece of Paper
Match or Lighter

Safety Note: Because the experiment involves fire, adult supervision is required.

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Egg in a Bottle Science Experiment Instructions

Step 1 – Remove the shell from the hard-boiled egg and place it on the mouth of the jar. Take a moment to make some observations. Why doesn’t the egg fit into the jar? Do you think it is possible to put the egg inside the jar? Do you think it is possible for the egg to move into the jar without touching it?

Step 2 – Remove the egg from the jar and set it on the table nearby. Make sure that you place it within reach because you’ll need to move quickly once it’s time to place the egg on the bottle again.

Step 2 – Get your strip of thick paper ready. Note that using thick paper is important because you need something that won’t burn too quickly when you light it on fire. We tore off a piece from an index card. Construction paper would also work nicely.

Carefully use a lighter to light the piece of paper on fire. Safety Note: Remember to always use safety measures when dealing with fire. Adult supervision is required.

Step 4 – Once the paper is burning, carefully but quickly drop it into the glass bottle.

Step 5 – Immediately after you put the paper in the bottle, place the egg on the top of the bottle.

Step 6 – Watch as the egg begins to slowly move into the bottle. If you are lucky the egg will stay in one piece as it moves into the bottle. Or if you are like us, the egg will eventually split as it is squeezed into the mouth of the bottle. Watch the Egg in a Bottle Experiment Video Tutorial to see what happens to our egg.

Were you surprised when the egg began to move into the jar? Do you know why it did? Read the how does this experiment work section before to find the answer.

Egg in a Bottle Science Experiment Video Tutorial

How Does the Experiment Work?

Air has mass, so it has other properties like pressure and density. Air is able to push or crush objects when given the opportunity. We don’t often see air pushing or crushing objects because air molecules surrounding objects push on objects equally in all directions. In this experiment, you get to see the power of air!

Air pressure is the reason the egg moves into the bottle without us touching the egg. Let’s go over exactly what happened.

When we started the experiment, the air pressure inside the bottle was the same as the air pressure outside of the bottle because the air inside the bottle and outside the bottle was the same temperature.

After we placed the burning paper in the bottle, the air inside the bottle began to heat up and expand. A few seconds after we placed the egg on top of the bottle, the fire went out and the paper stopped burning. This caused the air inside the bottle to cool down and contract.

When the air contracts, the air pressure inside the bottle becomes less than the air pressure outside the bottle. This gives the higher air pressure outside of the bottle the opportunity to push the egg down into the bottle.

I hope you enjoyed the experiment. Here are some printable instructions:

Hard Boiled Egg (Shell Removed)

Instructions

Position the egg near the empty bottle. This is needed because you have to move fast once it is time to place the egg on the bottle.
Take a strip of thick paper. Think paper is important, because you need something that won’t burn too quickly when you light it on fire during the next step. Helpful Tip: I used a piece of index card. Construction paper would also work nicely.
Light the piece of paper and drop it into the bottle. Remember to always use safety measures when dealing with fire.
Once the paper is burning, carefully but quickly drop it into the glass bottle.
Immediately after you put the paper in the bottle, place the egg on the top of the bottle.
Watch as the egg begins to slowly move into the bottle. Helpful Tip: If you are lucky the egg will stay in one piece as it moves into the bottle. Or if you are like us, the egg will eventually split as it is squeezed into the mouth of the bottle. Watch the Egg in a Bottle Experiment Video to see what happens to our egg.

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Egg in a Bottle Experiment – Two Easy Methods

The Egg in a Bottle experiment is a classic science project that demonstrates the principles of air pressure in a fun and visually appealing way. Here are two different methods for performing this project, each highlighting how changing temperature in turn changes air pressure and forces a hard-boiled egg into a bottle.

Egg in a Bottle Experiment Materials

Glass bottle with a neck slightly narrower than the egg’s diameter
Peeled hard-boiled egg
Matches or lighter
Small piece of paper

Finding the right size of bottle is a challenge. Remember there are different sizes of eggs available for sale. A sturdy plastic bottle is an option instead of glass, but sometimes the temperature and pressure change deforms the bottle.

Egg in a Bottle Using a Burning Piece of Paper – Method #1

Preparation: Peel the hard-boiled egg.
Ignite the Paper: Light a small piece of paper using matches or a lighter. Just using a wooden match works too, but a piece of paper typically burns longer and changes the temperature inside the bottle more.
Place the Paper in the Bottle: Quickly drop the burning paper into the bottle.
Position the Egg: Immediately place the peeled egg on the neck of the bottle. If you like, wet the egg with water so it is a bit slippery. Sometimes this helps a larger egg fit through a smaller hole.
Observation: After the flame goes out, the temperature inside the bottle cools and the egg slides into the bottle. Note: the egg does not enter the bottle because fire consumes oxygen! Oxygen merely rearranges into other compounds.

Explanation

When you drop the burning paper into the bottle, it heats the air inside. Heat gives molecules kinetic energy so they move more rapidly and have an increased number of collisions with the wall of the bottle. In other words, heat increases the air pressure inside the bottle . When you place the egg on the bottle, it seals it. Fresh air does not enter the bottle, so the flame consumes the oxygen and then goes out. As the air cools down, it contracts, creating a lower pressure inside the bottle compared to the outside air. The higher external air pressure pushes the egg into the bottle.

Egg in a Bottle Using Hot and Cold Water – Method #2

Heat the Bottle: Place the bottle in hot water, which heats the air inside. (Do not submerge the bottle and fill it with water.)
Position the Egg: After a few minutes, remove the bottle from the hot water and quickly place the peeled egg on the neck of the bottle. (If you like, place the egg on the bottle and then heat it. It makes no difference.)
Cool the Bottle: Immerse the bottom of the bottle in cold water.
Observation: The air inside cools and contracts. The outside air has a higher pressure than the air inside the bottle, pushing the egg through the bottle opening.

Heating the bottle with hot water expands the air inside the bottle. Some of it escapes the bottle. The egg seals the bottle. When you place the bottle in cold water, the air inside cools down and contracts, creating a lower pressure inside the bottle. The higher external air pressure pushes the egg into the bottle.

How to Get the Egg Out of the Bottle

There are ways of getting the egg back out of the bottle without breaking it up. Here are three methods:

Method 1: Reversing the Pressure

Tilt the Bottle: Turn the bottle upside down so the egg is at the neck.
Blow Air into the Bottle: Carefully create a seal around the bottle’s mouth with your lips and blow air forcefully into the bottle.
Increase Pressure: The increased air pressure inside the bottle pushes the egg back out through the neck.

Method 2: Lubrication Method

This method works if there is only a small size difference between the egg and the bottle opening.

Add Lubricant: Apply a thin layer of cooking oil or dish soap around the neck of the bottle and the surface of the egg to reduce friction.
Position the Bottle: Turn the bottle upside down so the egg is at the neck.
Gently Shake: Gently shake the bottle. The force of shaking helps slide the egg out. The lubricant makes it easier for the egg to pass through the neck of the bottle.

Method 3: Temperature Change

Position the Egg: Tilt the bottle upside down so the egg is at the neck.
Heat the Bottle: Once the egg is in the bottle neck, carefully change the bottle’s position so you can heat it. Submerge the bottom of the bottle in hot water and heat the air inside. As the air expands, pressure increases and pushes the egg out.

Of course, there is a chance these methods won’t work if the egg is too big. If you really need the egg removed and pressure is not working, insert a stick or wire into the bottle, break the egg, and shake out the pieces.

Relation to the Ideal Gas Law and the Combined Gas Law

The gas law that predicts the behavior of the egg in a bottle experiment is the Combined Gas Law , which is a special case of the Ideal Gas Law .

The equation for the Ideal Gas Law is PV = nRT, where:

P is the pressure
V is the volume
n is the number of moles of gas
R is the ideal gas constant
T is the temperature

In this experiment, the burning paper or hot water increases the temperature (T) of the air inside the bottle. According to the Ideal Gas Law, if the volume (V) of the bottle remains constant, an increase in temperature results in an increase in pressure (P). When you place the egg on the bottle and the air inside cools, the temperature decreases, leading to a decrease in pressure. The external air pressure (higher P) then pushes the egg into the bottle to equalize the pressure difference.

For the most part, the number of moles of air, volume of air (volume of the jar), and ideal gas constant remain the same throughout the project. This makes using the Combined Gas Law possible. The Combined Gas Law is a rearrangement of the Ideal Gas Law that combines Boyle’s Law, Charles’s Law, and Gay-Lussac’s Law. The Combined Gas Law is given by:

P 1 V 1 /T 1 = P 2 V 2 /T 2

P is the pressure of the gas
V is the volume of the gas
T is the temperature of the gas (in Kelvin)
Subscripts 1 and 2 refer to the initial and final states of the gas, respectively.

So, if volume remains the same, the equation only balances out when temperature and pressure both increase or both decrease.

Method 1: Using a Burning Piece of Paper

The burning paper heats the air inside the bottle, increase the temperature (T 1 ).
As the temperature increases, the pressure (P 1 ) inside the bottle also increases.
Some of the air escapes the bottle because of the increased pressure. But, it’s not enough to affect the outcome.
The flame consumes the oxygen and the fire goes out, decreasing the temperature (T 2 ) to decrease.
As the temperature decreases, the pressure (P 2 ) inside the bottle decreases. A common misconception is that the pressure decreases because the flame consumes oxygen, forming a partial vacuum. This is incorrect because no oxygen is lost. Instead, combustion forms carbon dioxide and water using carbon and hydrogen from the match or paper. The number and type of atoms inside the bottle remains the same.
The volume of the bottle (V) remains constant, so the decrease in pressure creates a partial vacuum inside the bottle.
The lower pressure inside the bottle (P 2 ) compared to the atmospheric pressure outside causes the higher external pressure to push the egg into the bottle to equalize the pressure difference.

Method 2: Using Hot and Cold Water

Heating the bottle in hot water increases the temperature (T 1 ) of the air inside the bottle.
The increased temperature causes the air to expand, and some air escapes the bottle, slightly increasing the volume temporarily.
Placing the bottle in cold water cools the air inside, decreasing the temperature (T 2 ).
As the temperature decreases, the pressure (P 2 ) inside the bottle decreases.
The volume of the bottle (V) is effectively constant after the initial escape of some air, so the decrease in pressure creates a partial vacuum inside the bottle.
Castka, Joseph F.; Metcalfe, H. Clark; Davis, Raymond E.; Williams, John E. (2002). Modern Chemistry . Holt, Rinehart and Winston. ISBN 978-0-03-056537-3.
Clausius, R. (1857). “Ueber die Art der Bewegung, welche wir Wärme nennen”. Annalen der Physik und Chemie (in German). 176 (3): 353–79. doi: 10.1002/andp.18571760302
Raff, Lionel M. (2001) Principles of Physical Chemistry (1st ed.). Pearson College Div. ISBN: 978-0130278050.

Egg in a Bottle – Air Pressure Experiment

April 21, 2021
10 Minute Science , 7-9 Year Olds , Physics

Science is amazing as it does wonders in our real life and around the world.

Today, Let’s explore “Egg in a Bottle”, which proves using simple science concepts anyone can put an egg into a bottle without touching it.

Yes, the egg can move into a bottle without any external help but with the help of science.

Objectives in this Science Activity

Using this experiment, children can learn,

1) Relation between Temperature and Pressure

2) Impact of air pressure on objects

3) Impact of air pressure in our daily activities

4) Properties of air

Amazed! Yes, though the experiment is quick and simple, it carries a lot of scientific information to inspire young scientists.

Egg in a Bottle – Experiment

Supplies required

1) One glass container or jar. Make sure the opening of the glass jar is smaller than the size of a boiled egg because to fit the egg perfectly instead of slipping into the jar easily. Milk and Juice bottles work well for this purpose.

2) A small piece of Paper

3) Fire source i.e. a candle or lighter or a matchbox

4) One or two boiled eggs

Things we need for egg in bottle experiment

Preparations

Just before the experiment, pick fresh and raw eggs and boil them until they turn hard. Probably, this step takes 7-10 minutes.

Once boiled, peel off the outer shell part of the boiled egg and wash it under tap water to remove any hard remnants attached to the egg. Then, keep it aside on the experiment table.

Simple Step by Step Instructions

Step-1: Place a clean and transparent glass jar on the experiment table.

And then pick a piece of paper and burn it using a lighter. Please make sure the paper is folded into a strip such that it is easy for you to drop it into the jar bottle.

Burn a paper - egg bottle experiment for kids

Step-2: When the paper catches fire, immediately drop it into the glass jar placed on the work table. You must drop the burning paper into the jar before the fire goes off.

Keep boiled egg on a bottle - Air Pressure Experiment step

Step-3: Now, Place the hard-boiled egg on top of the glass jar opening perfectly. Then observe the results.

Results: You will observe the egg slowly moving into the bottle. At times, the egg will go into the glass bottle as it is without any breakages, but sometimes it may spill while squeezing into the bottle.

Egg in bottle Science Experiment - Result

Note: If your egg fails or feeling difficult to slip down into the bottle, then you can apply vegetable oil around the neck of the bottle. Greasing oil helps the egg to move into the bottle easily.

Are you surprised watching an egg going into the bottle without any help from external forces? Do you want to learn that magical science trick? Then, let us discuss how this simple science activity worked out very well.

The Science Concepts behind The Egg in a Bottle Experiment

Air is a matter of substance, and hence it contains weight and other assets like density and pressure.

Generally, the air surrounding us or objects does not show any pressure because it surrounds with equal pressure.

But when there is additional pressure in the air, it starts showing its pressure through moving objects by push and pull trials.

In this science activity, we will observe that air shows its pressure when the opportunity is given.

Egg moving into the bottle without touching by external sources proves that air pressure is acting upon it. Let us discuss it in detail.

Before the experiment begins, the pressure of the air surrounding and inside the jar is the same as it is equally distributed.

That means the pressure inside and outside the glass bottle is the same at the beginning of the experiment.

But when we placed the burning paper into the glass bottle, the air inside the jar starts to expand. Because air molecules expand when it gets warmed up, and this is the specific characteristic of air.

And as soon as the egg is placed upon the opening of the glass bottle, the fire goes off, and the air molecules begin to cool down.

As the air molecules cool down, they start contracting themselves by lowering the air pressure inside the glass bottle.

That means there is a difference in the air pressure existing inside and outside the glass bottle.

Because there is less air pressure inside the bottle. The egg slowly squeezes into the bottle as the outside pressure pushes it from outside.

Yes, when the air molecules inside the bottle cool down, it offers more space to welcome additional air molecules.

In this process, the outside air molecules rush into the bottle to fill the spaces. So, it keeps pressure on the egg and helps it slip down into the bottle.

Extension Ideas

You can try out the experiment using other supplies such as boiling water and a balloon.

1) Use boiled water instead of paper inside the bottle and do the experiment

2) Try out using an inflated balloon filled with water in the place of a boiled egg.

Interesting Air Pressure Activities for Kids

Balloon in a Bottle

Crushing Can Experiment

Drip Drop Water Bottle – Science Behind Water Dispenser

Balloon in Hot and Cold Water

Tips to Teacher s

Here are the important questions a teacher can ask to make the students involved completely during the experiment. And to encourage them to participate in revealing and understanding the science behind the experiment.

1) What made an egg move into the bottle without touching it?

2) Why only eggs must be used in this science activity?

3) Are there any other possibilities to change the pressure of the air inside and outside the bottle?

4) Will the egg come out of the bottle again? If Yes, How?

5) What are the properties of air that made the egg move into the bottle?

Safety Measures

As we are dealing with fire, children need to be very careful while performing this activity. It is better to put on their safety guards even though an adult or teacher performs the activity. Adult supervision is a must when a child is performing this activity on his/her own.