Play Ideas

Ingredients:

Raw EggWhite Vinegar

Tools / Utensils :Clear drinking glass or plastic cup1.

Method

Gently place an egg inside the glass.Fill the glass with vinegar until the egg is completely covered.Leave the egg in the vinegar for a full 24 hours.You can come back to observe the egg every few hours.Note down your observations.After 24 hours, gently pick up the egg and rub off the shellunder running water.You should get a translucent bouncy egg.

1.2.3.4.5.6.

7.

24H

Science Concepts

A chemical compound that tastes sour and forms a water solution whichturns blue litmus paper red.

Acid -

A chemical reaction is a process in which one or more substances areconverted to one or more different substances. (When the vinegar isadded into the glass with the egg, the egg become translucent)

Chemical Reaction -

PARENT GUIDE

In this experiment, we explore chemical reactions between vinegar and the eggshell.

Eggshells are formed almost entirely of calcium carbonate (CaCO 3 ) crystals. It is a semipermeable membrane, which means that air and moisture can pass through its pores. The shell also has a thin outermost coating called

the bloom or cuticle that helps keep out bacteria and dust.

The vinegar (acetic acid) reacts with the eggshell (calcium carbonate) to produce a water- soluble compound,calcium acetate, and carbon dioxide gas (which you will see as bubbles on the eggshell during the experiment).

Ask your child what they observed at each stage of the project.

Learning Outcomes (Refer to Learning Outcome Template)

Ask your child what do they think happened?

- Why is the vinegar able to dissolve the eggshell?Answer:

2. Comprehension

The acidic properties of the vinegar reacts with the eggshell whichis a base. This is known as a neutralization reaction.

- How does the egg hold its shape after it loses its shell?Answer: A thin membrane, which is beneath the egg, keeps the egg together.

If this membrane breaks, the egg whites and yolk will spill or burst out.

Ask your child what they observed at each stage of the project?

1. Observation

- What is visible when we pour vinegar onto the egg? Why do you see that?Answer: You can see little bubbles forming around the eggshell. These

bubbles are carbon dioxide gas which is one of the products ofthis chemical reaction.

- After a couple of hours, what can we observe about the eggshell?Encourage your child to touch and rub the egg gently.Answer: The shell is beginning to get softer as it dissolves, and the egg

has increased in size as it has absorbed some of the vinegar.

- After 24 hours, what is different about the egg?Answer: The eggshell would have completely been dissolved. It is no longer

a hard shell. The egg feels squishy and it is bouncy. Be careful whenbouncing the egg, it may still break.

Did you face any challenges?

- Did any egg break during the experiment? (eggs tend to crack upon impact and once the membrane is exposed, it might be punctured by fingernails oranything sharp, so be gentle).

- What did you do when the shell didn’t dissolve after 24 hours?

Did you try using different acidic solutions ?

- Take note of the duration before the shell completely dissolves.

- How long did it take to dissolve the eggshell?

4. Testing & Improving

Did the egg become translucent after 24 hours?

- Do you think the quality (brand) of the vinegar played a factor ?

Did the smell of vinegar put you off? What does vinegar smell like?

- Acids have a sourish smell and taste.

3. Evaluation

Turn off the lights and shine a torchlight on the bouncy egg.

You can also try adding food colouring to the vinegar. What do you think might happen?

The eggsperiment we are about to explore demonstrates how chemical reactions can happen between 2 substances.

The result is very surprising and fun. We don’t normally pay much attention to eggshells.This time around, we want to make the shell disappear using some chemical engineering concepts.

EGGSPERIMENT