sugar egg experiment

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Osmosis and Shrinking Eggs!

August 29, 2011 By Emma Vanstone 15 Comments

Welcome to a very eggy week on Science Sparks! Shrinking eggs is the first of 3 egg based experiments, so if you like this one, pop back later in the week to see what else we have been up to! This experiment looks at osmosis .

Osmosis is the net movement of water molecules across a partially permeable membrane from a region of higher water concentration to a region of lower water concentration.

Water molecules flow from one side of a membrane to the other until the concentration of water molecules on both sides is equal.

What you need:

• Two glasses

This experiment has 3 stages:

Remove the shell from the egg with vinegar

Shrink the egg by placing it into a concentrated sugar solution

Grow the egg by placing it in water.

Remove the shell from an egg

We need to remove the shell to expose the semi-permeable membrane of the egg. This can be done by placing the eggs in a cup of vinegar, so they are totally covered for about 24 hours. After this time wash the egg rubbing away the remaining bits of the shell.

Shrink and grow the egg

Make up a concentrated sugar solution by dissolving sugar in water. Place one egg in a glass of water, and the other in the sugar solution. Our sugar solution looks quite dark as I used brown sugar. Note how the egg in the water sinks to the bottom of the glass while the one in the sugar solution floats. This is because the sugar solution is denser than the water.

• Leave for another 24 hours. You can see the egg in the sugar solution looks much smaller than the one in the water.

Prick the egg from the water with a fine needle and watch a jet of water shoot out!

• Put the shrunken egg in water and watch it grow as it reabsorbs the water, this might take a few hours.

Why does the egg shrink and grow?

The sugar solution is much more concentrated than the water, this is because it contains dissolved molecules of sugar. The dissolved sugar molecules cannot pass through the semi-permeable membrane of the egg, but the small water molecules can. The water moves from the less concentrated egg solution to the more concentrated sugar solution until the concentration of water is the same on both sides. Therefore water moves from the egg to the sugar solution, and the egg shrinks.

When the shrunken egg is placed back in water, the concentration of water inside the egg is lower than the water, so water moves from the water to the egg, making the egg increase in size.

When we pricked the egg that had been in the water, water shot out of the egg. This is because the egg has absorbed water, and so the inside of the egg is under more pressure than usual.

The egg shell dissolves in the vinegar as the acetic acid in the vinegar reacts with the calcium carbonate of the shell. Carbon dioxide is given off during this reaction so you should see bubbles of gas escaping.

Extension Tasks

Weigh the eggs after removing the shell, after they shrink and again after they reabsorb water to see how much water is lost and gained at each stage.

Try adding food colouring to the water and watch as the eggs absorb the coloured water.

Soak a boiled egg in vinegar, this should make the egg so rubbery it will bounce ( from a low height ). You can also bounce a non-boiled egg that has been soaked in vinegar.

Don’t forget to wash your hands after handling raw eggs!

Last Updated on January 18, 2023 by Emma Vanstone

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.

Reader Interactions

August 29, 2011 at 6:31 pm

this looks great….I won’t promise to do it as I still have 2 avocado stones on my kitchen table!

August 30, 2011 at 12:41 pm

Do it!!! xx

September 05, 2011 at 2:31 pm

How interesting. Thanks for linking up and sharing this idea on my site.

Sharing a link over on Facebook.

January 25, 2012 at 3:59 pm

Do you use hard boiled eggs? How does the egg not break when removing the shell? Does the vinegar cook it? Thanks

January 25, 2012 at 9:24 pm

The egg is not cooked inside, it is liquid, the vinegar removes the shell, but leaves the outer membrane which keeps the egg in tact.

April 14, 2012 at 7:46 pm

What age is this appropriate for?

April 15, 2012 at 1:39 pm

My children were 3 and 4 at the time, I did everything for them, but they were very interested in it.

June 19, 2012 at 3:00 am

Oh wow! What a neat experiment! Thank so much for sharing with Tuesday Tots. Pinned 🙂

November 28, 2012 at 7:31 pm

This looks really cool! How much sugar did you use for the solution ?

March 19, 2013 at 5:06 pm

These all look like fun! My 11 yod and I were just wondering how long do you soak the hardboiled egg in vinegar to be able to make it rubbery and able to bounce?

March 20, 2013 at 2:12 pm

It usually takes a couple of days and you’ll need to wash away the shell remnants.

March 09, 2015 at 9:49 am

Sorry but I’m a biology student yr11, osmosis is actually the diffusion of water from a high concentrated region to a low concentrated region. I’m sure you made a mistake because my textbooks and what I’m being taught all the opposite of what is in your statement. Correct me if im wrong, I did this experiment last week and I’m writing a lab report and needed some more explanation from the internet. Sorry, wouldn’t want other people getting confused.

July 20, 2017 at 8:18 am

hi Dear. where in the text did you find the wrong statement opposite to the osmosis law, i.e., water diffusion from high to low concentration? maybe by the term concentration which was only used for the sugary liquid and it meant -i think- the concentration of big sugar molecules, if it is high then the water is low and if they are low, then the water is high. so you’d actually need to reverse the low/high adjectives to define how much water you have, if you were reading that part about the sugary liquid So i guess whenever you see the term concentration, just imagine they ar talking about the sugary liquid and not the water (pure water)

July 20, 2017 at 8:20 am

hi Dear. where in the text did you find the wrong statement opposite to the osmosis law, i.e., water diffusion from high to low amount? pls notice: amount and not concentration. The term concentration is only used in the sentences regarding the sugary liquid here and not the pure water maybe by the term concentration which was only used for the sugary liquid and it meant -i think- the concentration of big sugar molecules, if it is high then the water is low and if they are low, then the water is high. so you’d actually need to reverse the low/high adjectives to define how much water you have, if you were reading that part about the sugary liquid So i guess whenever you see the term concentration, just imagine they ar talking about the sugary liquid and not the water (pure water)

May 02, 2017 at 2:37 am

very fun and love you guys

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Floating Egg Science Experiment ( Using Salt, Sugar & Saline Water)

• December 10, 2020
• 10 Minute Science , 5-6 Year Olds , 7-9 Year Olds , Physics , Rainy Day Science

Hello everyone! Today we have come up with simple ‘ Floating Egg Science Experiment with a twist’ that can be done within 5-10 minutes.

My kids call it as a pre-breakfast activity. This is an easy and funny experiment to teach density for kids .

We know that some things float in the water and some others not. Do u know why the things sink in the water!? Let us learn something about floating science using eggs.

Floating Egg Experiment

This activity is a cool way to learn the concept – density! We are going to perform the experiment with four different liquids to understand the science behind floating objects in water.

We commonly see that eggs sink when we put in the water. What is the reason behind this!? Does egg sinks the same way when dropped in other liquids? We will perform a simple activity to learn the science behind it.

Try our 20+ Egg Science Experiments

Materials Required for the Activity

• Saline water (You can find saline water in any of the local pharmacies)
• Four glass jars (Either you take glass jars or beakers, make sure they are tall and wide enough to drop an egg)
• Four Raw Eggs (Ensure the eggs are not broken or given any crack to avoid the unnecessary mess with the leaky eggs during experiment)
• Fill one tall drinking glass or glass beaker about ¾ full of water.

• In the same way, fill the other glass with salt water. To prepare salt water, put 1-2 cups of salt in 500ml of water. Stir it with the spoon. That’s it. You are done with making salt water.

• Now it is second drinking glass turn! Fill it with sugar water. Prepare the sugar water same like how we made salt water in previous step.

• Saline water! Yes, we are using saline water as well to observe the floating science with eggs. Fill the fourth glass beaker with saline water.

• Finally, we have arrived to the kid’s favourite step i.e. dropping egg into the tall drinking glasses.

My younger daughter is eagerly waiting for my instructions to drop the egg in the liquids. When I said so, she carefully dropped the raw eggs into the four glasses filled with four different liquids each.

Ask your kids to observe the results that in which liquid the dropped eggs are floating or sinking.

On the initial test, we only had egg floating in the salt water. The sugar water was not dense enough to make the egg float. So we tried to add more sugar to the already prepared sugar solution.

Finally we made the egg float in the sugar water as the water is now more dense due to the added sugar.

How Does the Floating Egg Science Experiment Work?

Let us discuss the results of our experiment. The raw egg dropped in the tap water sinks immediately as soon as it is dropped. On the other hand the egg in the salt water floats.

We observe the same results with the sugar water as well. The raw egg floats nicely in sugar water as well.

How about our egg in the saline water? The egg didn’t float surprisingly in the saline water.

Now let us discuss on what made the eggs in salt & sugar water float and why the egg in normal tap water and saline water sink!?

Science behind floating egg

The egg in the glass of regular tap water sinks to the bottom because the density of egg is more compared to density of water.

Why the egg in salt water floats? When the salt is added to the water, it increases the density of the water and hence the density of the egg slowly becomes lesser than the salt water.

You are dissolving the more the salt into the water means you are increasing the density of water. The denser the liquid is the easier for the object in the water to float.

The same formula applies to the sugar water. The density of sugar water is more than the density of egg.

On the other hand, saline water is made of salt and water. However, the density of the saline water that we used seems to be lower than than egg. Thus it floated in the sugar water and sinked in the saline water.

Density is a concept dealing with how closely a substance is packed to be together.

We will compare this concept with our daily life things. For example: consider we have two bowls one is filled with salad and the other is with rice.

Both are of taken in same quantity but we feel the salad bowl is lighter than the rice bowl because the ingredients are packed tightly in the rice bowl than the salad of lettuce and vegetables which are very light in nature.

In the same way, the molecules in the salt, sugar, and saline water are packed more closely and makes the salt, sugar, and saline water denser than the water where the molecules are packed lighter thus making it less denser.

Even the egg has some density but less than the salt water and hence the egg floats in salt, sugar, and saline water.

So, when you go to swimming pool or beach or ocean, observe that you will float easily and lightly compared to salt water. The denser the liquid, the easier you will float! Amazing right!?

Experiment Extensions

Try different liquids and different substances to dissolve in the water in order to make an egg float.

Try these Density Science Experiments :

9 Layer Density Tower

Hot & Cold Water Experiment

DIY Sugar Density Rainbow

Oil, Food Color & Water – Fireworks

How to make Lava Lamp

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It's the Great Egg-speriment Charlie Brown!

Updated: Oct 4

The *Autumn* Science Club is a collection of fun, kid-friendly science experiments and STEM projects explained.

As school ends, millions of kids are released from a strict schedule of learning and innovating. As a kid who grew up with a science teacher, a mom, and an engineering dad, I spent my summers doing science experiments and STEM projects. I came out of every summer with many new skills and knowledge of the world around me. Now, working with young kids at the library, I teach these experiments to others.

Two things come to mind when I think of fall: It’s the Great Pumpkin, Charlie Brown! And the egg experiment my mom does every year in her classroom. The egg experiment is one of the most fun science experiments that my mom does. I have been helping her test out this experiment every year for a very long time. She does several tests with these eggs in her life science class.

The hard shell of an egg is made of calcium carbonate. The thin and flexible membrane inside of the egg is made of a material that won't dissolve in vinegar. White vinegar is made out of 96% water and 4% acetic acid. This dissolves the hard shell and produces water, carbon dioxide, and calcium acetate. The membrane is left and holds the egg together and, makes it bouncy and squishy.

Glass or plastic cup

Plastic wrap

Sugar syrup

Egg-Experiment: Phase One

Measure the egg with a ruler and weigh it. Record this so you can compare after.

Put the egg in a cup and fill it with vinegar to cover the egg and then some.

Cover the cup with plastic (so your house won't smell like vinegar)

Wait 48 hours and watch as the hard shell of the egg starts to dissolve.

Drain the vinegar and hold your egg very carefully. Put a bowl or tray under the eggs and have paper towels on hand because the egg might burst. You might have to rub some of the shell or keep the egg in the vinegar for a few more days. The egg will be very squishy as the hard shell is gone.

Measure and weigh the egg again. The egg will be slightly bigger because some of the water in the vinegar passes through the egg's membrane now that the hard shell isn't in the way.

The next part of this experiment is to deflate the egg.

To make a simple syrup, add one cup of water to 1.5 cups of sugar in a saucepan and cook it till it dissolves. Cool the mixture before adding it to the egg.

Rinse off the egg and add it to a cup of simple syrup.

Wait for a day or two.

Very gently pick up the egg. It will feel very deflated. Be very careful because this is the point where it will burst. The egg is deflated because all of the water has been sucked out of it by the sugar.

Phase Three

There isn't much you can do with the sack of an egg, so let's add the water back to the egg.

Add the egg to a cup of water, add a few drops of food coloring, and wait a couple of days.

When you take the egg out of the water, it becomes bouncy and squishy like it was before.

At this point, you can keep going back and forth between the sugar and the water to inflate and deflate the egg, but if you're one with the experiment, you can pop the egg. It will be very messy and possibly colored if you add food coloring.

Why doesn't this happen to a regular egg? The hard shell protects the membrane, which is more porous than the hard shell. Osmosis is when liquid passes through the membrane so that the outside and inside liquid are the same. The membrane is exposed when the vinegar is added the first time, and then water can pass through more than it could before.

https://liveseasoned.com/eggsperiment-time/

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Floating Egg Science Experiment

Can you make an egg float in water? In this simple science experiment, we take just a few minutes to test the laws of density and discover just how easy it is to make an egg float!

Below you’ll find detailed instructions and our demonstration video as well as the scientific explanation of “why it works.” We’ve also included a more ideas to explore the concept a bit further.

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

Supplies Needed

• 2 Tall Drinking Glass

Floating Egg Science Lab Kit – Only $5

Use our easy Floating Egg Science Lab Kit to grab your students’ attention without the stress of planning!

It’s everything you need to  make science easy for teachers and fun for students  — using inexpensive materials you probably already have in your storage closet!

Floating Egg Science Experiment Instructions

Experiment Setup – Start with some observations about the eggs. Note that they are both raw eggs and have a similar size and weight. Then ask some questions. Do you think that the eggs will sink or float when placed in water? Do you think it’s possible to make them float? If so, how? Write down your hypothesis (prediction) and then follow the steps below.

Step 1 – Fill a tall drinking glass about 3/4 full of water and carefully place the egg into the glass. What happens to the egg? That’s right, it sinks to the bottom.  

Did you know there is a way to make it float? Continue on in the experiment to find out how. 

Step 2 – Fill another tall drinking glass about 3/4 full of water. 

Step 3 – Add 3 Tablespoons of salt to the water and stir until it is completely combined. What do you think will happen if you place the egg into the glass with the salt water? Write down your hypothesis (prediction) and then test it to see if you were right. 

Step 5 – Next carefully place the second egg into the glass with the salt water. What happens to the egg? That’s right, it floats. Take a moment to make some observations. Why do you think one egg sinks and the other egg floats?

Find out the answer in the how does this experiment work section below.

Video Tutorial

How Does the Floating Egg Science Experiment Work

Why does the egg sink in regular tap water, but float in saltwater? The answer lies in the density of water!

Density is a measure of the mass per unit volume of a substance. Simply said, how much “stuff” in a given volume. Water has a density of 1 g/mL (g/cm3). Objects will float in water if their density is less than 1 g/mL. Objects will sink in water if their density is greater than 1 g/mL.

The egg will sink in regular tap water because the density of the egg is greater than the density of water. The egg’s density is only slightly higher than water at 1.03 g/mL, but that is enough to make the egg sink.

When you add salt to the water, you are increasing the density of the water by adding more mass (or stuff) in the given volume. You don’t really change the volume of the water by adding salt. By adding enough salt, you increase the density of the water so that it is higher than the density of the egg and the egg will float!

Other Ideas to Try

Try this experiment again, but instead of using an egg use a potato slice or a carrot slice. You will have to play around with the amount of salt you add to the water because all objects have their own unique density. Add salt a tablespoon at a time and mix well until you cannot see any salt in the solution, then add your object to see if it floats or sinks. Remove your object and keep adding salt until you can get your object to float. To make it a true science experiment, create a data table to keep track of how much salt you add to the solution.

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

• Drinking Glass

Instructions

• Fill a tall drinking glass about 3/4 full of water
• Place the egg into the glass of watch and watch it sink
• Fill another tall drinking glass about 3/4 full of water
• Add 3 Tablespoons of Salt and stir until combined
• Place the egg into the glass and watch it float

Reader Interactions

April 3, 2019 at 2:58 pm

i love this experiment

January 23, 2020 at 11:14 pm

I really loved doing this experiment with my class

August 26, 2020 at 2:59 pm

The egg floats because the density of the salt water changes to be greater than the egg and the density of the egg becomes less dense so then the egg floats. But when you put an egg in tapwater the density of the egg is greater than the density of the tapwater which makes the egg sink.

January 20, 2022 at 11:33 am

bro I loved this experiment it was amazing!!! I tried it out with my friends and it worked! Thank you!

February 10, 2022 at 7:19 pm

this is very helpful thank you

March 7, 2022 at 9:56 am

i loved this experiment : )

April 16, 2023 at 11:35 am

I love doing this experiment at home

May 1, 2023 at 9:00 am

It’s amazing thank you for sharing.

November 3, 2023 at 10:18 am

This is my science fair experiment! YAY!

November 25, 2023 at 7:41 am

wow what a great experiment m!!!

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Science Experiment: The Floating Egg

• Experiment , Pre-School , Science Experiments , Toddler

11 Comments

As I hovered the egg over a jar of water, I asked my 3.5 year old, “Will it sink or float?” and it reminded me of Dave Letterman’s funny sketch, “Will it Float?” Have you seen it? This science experiment is really easy to set up + clean up, and the lesson learned on the density of water actually stuck with my 3-year old daughter long after the experiment was over. Fun and success!

• Clear container: I used a wide jar, but a tall glass would work and you won’t need as much salt
• A few cups of salt
• Spoon to mix the solution

Place the egg in plain water and talk about whether or not it floats. Pretty simple — it most definitely sinks!

Start adding salt to the water. We added ours little by little, and tested the solution by adding the egg back into the water. My 3 year old poured while my 1-year old mixed. I love these moments when they work and play side-by-side.

Finally, it floats!

My little one loved this step, as she could finally reach the egg, and had some fun picking it up and dropping it back into the water where it “bounced.”

The Science behind the Experiment

The egg won’t float in regular water because it’s heavier than the water. But adding salt to the water makes the water more dense than the egg, and it floats! We have a book called “Let’s Visit Israel,” and my 3-year old will talk about this phenomena when we reach the page about floating in the Dead Sea.

Taking it one step further

Steve Spangler Science has a great idea for dragging this out into one more step. Fill half of a tall glass (that an egg will fit in) with this salty solution and then slowly pour plain tap water down the sides of the glass, being careful not to mix the two solutions. Gently drop the egg in the solution and watch it sink past the plain water, only to stop on top of the salty water! How cool is that?!

What a fun experiment! One of my (undeclared) goals this year is to do more science experiments with my daughters. We just did the naked egg experiment and that was fun, we’ll really have to give this a go. I LOVE Steve Spangler!

Steve Spangler is a favorite!  We love to do the naked egg experiment as well!

Could also be used to find out if an egg is old – stale eggs will float!

We did this experiment when we learned a bit about Israel (I go there quite often on business trips). I called it “The Dead Sea” experiment. Our personal favorite is penny cleaning.

Very cool! Can’t wait to try this with my kids. Have you left an egg soaking in white vinegar to see what happens? It’s an easy, interesting experiment (and I won’t give the final result away for anyone curious to give it a try). 🙂

Whoops, just read the other comments and it sounds like everyone knows about the naked egg trick already! Oh well, it’s a good one.

Great experiment! Be careful to use fresh eggs however, because the older an egg gets the more air is contained inside the shell, which will make it float. The “sink or float” experiment is actually how we test to see that our eggs are still fresh!

one of our facebook fans said you can do the same thing with a CARROT!!!  give it a go!  who knew??!?!

i love this experiment

my gob this very nice experiment

thanks i learned in this experiment

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Floating Egg Experiment

Will an egg float in fresh or salt water.

Will an egg float in fresh or salt water? The Floating Egg Experiment is an easy hands-on investigation that can be done in your own kitchen! I have used this lab before as a class demonstration, group lab investigation, and with my own kids at home. There are several science terms and concepts that can be taught in this experiment including density, solutions, mixtures, saturation, concentration, mass, and the list goes on. Scroll to the bottom to download your own Floating Egg Experiment Lab Sheet!

*Don’t miss out on the Salt Water Density Lab featuring a free observation lab sheet too! And be sure to check out all of our  FREE Science Resources including our  Labs & Experiments !

As a Christian Book and Amazon affiliate, we may earn commissions from qualifying purchases. Thank you for your support. As always, we only recommend items that we truly feel will benefit your homeschooling experience. We appreciate it.

Floating Egg Experiment Introduction

Before conducting the experiment, there are a few things you should cover with your students to create a meaningful learning experience. First, spend time talking about the terms below. We discuss the meaning of salinity and a homogeneous mixture amongst other concepts. Since this investigation is demonstrating the difference in density between salt water (oceans) and fresh water (rivers, lakes, ice), it works well with our Water Distribution Unit .

Important Terms and Facts

– Salinity  describes the amount of salt dissolved in water. Saline water is water with salt dissolved in it. 

– A homogeneous mixture  is a type of mixture where a solute (salt) is dissolved into a solvent (water). This type of homogeneous mixture is called a solution . 

– Density is the amount of mass in volume. Volume is the amount of space something takes up. 

– Buoyancy is a force on an object making that object rise or move forward.

Floating Egg Experiment Lab Sheets

Write hypothesis.

Once you have introduced the key terms in the Floating Egg Experiment, make sure the students are given the following facts and the FREE FLOATING EGG EXPERIMENT LAB SHEETS.

• Water has a density of 1 g/mL (g/cm3).
• Objects will float in water if their density is less than 1 g/mL.
• Lastly, objects will sink in water if their density is greater than 1 g/mL.

After giving your students this information, guide them to write a hypothesis for the posing question, “Will an egg float in salt or fresh water?”

For example, their hypothesis could read like this:

If I add 1 TBSP of salt to every ½ cup of fresh water, a raw egg _____________________________ float.

Students will plug in the words, “will” or “will not,” in the blank of the hypothesis.

Identify Variables

Identifying variables in an experiment is something that takes most students practice. It is a good idea to continuously review the following terms. Check out our  Scientific Method unit to get more practice.

Manipulated Variable – variable that is different in the experiment. It is the thing that is manipulated. *In this case, the manipulated variable is the amount of salt added to the water.

Responding Variable – variable that is being tested. It responds to the manipulated variable. *Hence, if the egg floats or not. 

Controlled Variable – variable(s) in the experiment that do not change or remain the same. *In this lab, the glasses and raw egg are the controlled variables. 

Review the experiment before conducting...

For you teachers, it is always advisable to try an experiment out first to ensure that it works the way it is supposed to. There is nothing worse than demonstrating in front of a group of students for an experiment to flop! It has happened to the best of us… yes, it has happened to me! Watch this video I found on YouTube to get a step by step of the experiment. It is pretty easy to demonstrate. 

I have used this experiment for years with the exception of the salt water with the fresh water on top. That aspect of the experiment was new to me. So, I too tried this at home before showing it to my students. *I wonder if it will work with glasses that aren’t quite so narrow at the bottom? Let’s see…

Gather Materials

The materials list is likely to all be found within your kitchen. I love experiments that do not require a tricky supply list. So, gather 3 raw eggs, water, salt, a spoon, 3 clear glasses, and a measuring cup and tablespoon come in handy.

Fresh Water first and then Salt Water

I always start demonstrating the egg sinking in the fresh water first. Next, you will show how adding salt to the fresh water will change its density. Thus, the egg will now float in the denser salt water. In the Egg Floating Experiment, I use 1 tablespoon of salt per 1/2 cup of water. This enables the students to measure more precisely. Some kids need the restrictions.

*On their lab sheets, students will draw and record observations and make conclusions.

Extended Learning...

This aspect of the Floating Egg Experiment is a new for me. I never did this in years past, but what a great addition. You can choose to demonstrate this last glass or the students can continue to follow the procedures on their lab sheet. In the end, take the time to talk about the science behind this experiment. This is where the science comes all together!

What's the Science behind it?

It’s very important that before, during, and after an experiment that you are explaining the science behind the experiment. If you skip this step, then the lab becomes merely a fun hands-on activity with no real science connections. The experiments are meant to help the students get past the surface and begin to soak in the abstract and unseen science behind it.

Glass #1 – The egg sunk to the bottom in glass #1 because the egg is more dense than the water. Hence, the egg has more mass in its volume than the water does. 

Glass #2 – The egg floats in salt water because the salt water is more dense than the egg. This means that the salt water has more mass in its volume than the egg does. The salt adds mass to the volume of the water creating a more dense liquid.

Glass #3 – When the egg is put in the cup, the glass is only half full with a mixture of salt and water. This causes the egg to float in the salt water instead of sinking. When plain water is added to the salt water, the egg remains in the middle of the glass because of density. The plain water is the least dense, then the egg, and the most dense is the salt water at the bottom of the glass.  

*When the floating eggs are pushed into the salt water, the eggs float right back up to the top of the salt water. This is due to buoyancy. The force of the salt water causes the egg to rise back up. 

DOWNLOAD FLOATING EGG EXPERIMENT LAB SHEETS

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John 4:14  – But whosoever drinketh of the water that I shall give him shall never thirst; but the water that I shall give him shall be in him a well of water springing up into everlasting life.

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