Science in the kitchen: Eggs and Vinegar

So, J asked if he could perform an experiment at home that he read about in one of his Horrible Science books. I had a look at it and realised that we had all the ingredients in our kitchen and nothing seemed explosive or particularly messy…so why not?

Warning: Science! Also puns. Lots of EGG-ceptional puns. You’re going to crack up. Seriously. Omelettin’ this happen, yo. 

J’s Question: What happens when you soak eggs in vinegar?

What we used to answer J’s Question:

  1. One hard boiled egg
  2. One raw egg
  3. Vinegar (we used apple cider vinegar, but white vinegar probably works best)
  4. Glass jars of roughly the same shape and size.

What we did to answer J’s Question:

1. Label the jars and place the respective eggs inside.

egg-vinegar-experiment

2. Cover each egg with an equal amount of vinegar and watch the science happen.

  • J’s Observation #1: Bubbles appeared on the surface of the eggs
  • EGG-CITING SCIENCE! The acetic acid in the vinegar reacted with the calcium carbonate of the eggshell, releasing carbon dioxide gas as bubbles!

experiment-science-egg-vinegar

3. Leave the eggs in the vinegar for three days. Check on the eggs and see if there is more science happening

  • J’s Observation #2:There is a yucky white scum floating on the surface of the vinegar
  • EGG-CELLENT SCIENCE! Calcium acetate is a the other byproduct of the chemical reaction between the vinegar and the eggshell, and is a white solid at room temperature.

4. Remove the eggs from the jars and rinse away the vinegar (and any residual eggshell) under running water. Remember to EGGS-ercise caution whilst doing this.egg-vinegar-experiment-science-membrane-diffusion

5. Place the eggs on a plate and allow them to dry. Compare the two eggs.

  • J’s Observation #3: Both eggs have a smooth and waxy surface. The raw egg is much bigger than the boiled egg (Debs G: It is EGG-ceptionally large) after it has been soaked in vinegar
  • EGG-STREME SCIENCE! The eggshell completely dissolved in the vinegar. Underneath the eggshell is the egg membrane. Some of the water from the vinegar has moved across the membranes to the inside of the raw egg, but the contents of the egg did not leak out. This is because the egg membrane is semi-permeable and allowed only certain sized molecules through. The egg membrane is stretchy, so the egg swelled as the water moved inside it. Water moved inside the egg because the contents of the egg contained less water than the vinegar outside the egg. The process where a solvent (such as water) moves from a lower concentration solution (such as vinegar) to a higher concentration solution (such as egg white) is called osmosis.

science-egg-vinegar-boiled-raw

 

6. Drop both eggs from increasing heights and see what happens.

  • J’s Observation #4: I can see the yolk wobbling about inside the raw egg but not in the boiled egg. When I dropped them, both eggs bounced but when I dropped them from very high up, the raw egg burst like a water balloon (Debs G: It was EGGsplosive). The raw egg is liquid, but the boiled egg is solid.
  • EGG-TRAORDINARY SCIENCE! Eggs are full of protein. Proteins are made up of amino acids. When the egg is boiled, the heat messes up the amino acid bonds that hold the proteins together and give them a particular shape and form. The egg protein changes in form and appearance, becoming hard and solid. When proteins change from their original form into a new form, this is called denaturation.

So, don’t be a chicken. Get cracking and hatch a plan to make Science happen in your own kitchen!

These are the yolks, kid. These are the yolks.

 

Advertisements

18 thoughts on “Science in the kitchen: Eggs and Vinegar

    • Oh, I did not dare to eat the eggs because they had been soaking in the room temperature for so many days, I was sure that they would be off. But you have a good point – maybe the vinegar would have pickled them enough to keep them fresh? That would be another interesting thing to think about if we ever do another eggs-periment!

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s