Changes

of

state

s of

matt

er

The b

ouncy

egg e

xperi

ment:

In this experiment I will

show you how the eggshell has changed

it’s state from a solid to

a gas.

My prediction:

I predict if you soak an egg in fizzy liquids the shell will turn into a squishy/bouncy solid. For my experiment I will be using

coke, orange juice and vinegar and soaking my eggs for 3 days. I think that they are all

going to become bouncy.

My experiment

First I put 3 eggs into 3 different cups. I then filled the glasses up, one with orange juice, one with vinegar and the other with coke.

My observations

Day 1:

The egg in the vinegar is the only one not floating and I could hear it cracking. Maybe it’s expanding. The vinegar egg was also covered in bubbles.

My observations

Day 2:

The eggs in the coke and orange juice still look normal. The egg in the vinegar had brown froth on top and the egg appears bigger.

My observations

Day 3:

I removed all the eggs from their liquids. What I noticed was the eggshell on the coke hadn’t changed. The orange juice eggshell had turned white but was still hard. The eggshell on the vinegar egg had completely dissolved leaving it soft and squishy.

My observations

Time to see if they are bouncy!

How does it work?The vinegar egg was the only one to change its state of matter, the hard eggshell dissolved leaving the egg squishy. The acid in the vinegar dissolves the calcium that’s in the shell. When the two come together they create a chemical reaction that breaks down the calcium carbonate and produces carbon dioxide, these are the bubbles we saw on the outside of the egg.

The clear skin on the outside of the egg is called the membrane which is now holding the egg together . The membrane is remarkable because it’s impressively tough. It contains keratin, which is found in human hair. The toughness explains why we can bounce rubber eggs.

The egg also absorbs the vinegar which makes it bigger. Whilst the acid in the vinegar is breaking down the eggshell, more water is moving into the egg than leaving.

We cannot reverse our experiment by replacing the eggshell but we can deflate our egg! By leaving the bouncing egg in golden syrup, in less than half a day our egg will deflate and shrivel.

Why didn’t they work?

I think that the coke never dissolved the eggshell because it lost it’s fizz. If we had put the egg in a jar with a lid, maybe the shell would have dissolved.

I think that the orange juice may have of worked if I kept the egg in the juice for longer. The egg changed colour but didn’t dissolve.