The Effect of an Acid on an Egg

Posted by Joyce and Jonathan

 Today we started our experiment. First we got an egg and vinegar. We used  Litmus paper to test the vinegar and it turned red to show the vinegar was an acid.

The Litmus paper turned red.

Next we poured some vinegar into a jar and then we gently dropped in an egg. The egg went bouncing up and down and then it began to float.We noticed some little bubbles forming around the shell.

Tiny bubbles of Co2 are forming on the shell of the egg.

Day 2 Today we checked our experiment. I saw that there were now many bubbles around the egg. These bubbles are caused by a chemical reaction between the vinegar and the calcium carbonate in the shell. Vinegar is an acetic acid and it is changing the egg shell into Co2. The carbon dioxide is escaping in the bubbles.

On Day 2 Hundreds of bubbles indicate that the chemical reaction is taking place.

Day 3

The egg is all soft and the bubbles are still surrounding it. It is horrible. There is a scum floating on the water as well as the egg. It smells very bad.

Day 4

The egg is still floating in the jar and it looks like that it increased in size. My teacher touched the egg with her finger and managed to rub away some brown. We took out the egg while we changed the vinegar and it looked much larger. If you felt the egg it felt squishy. If you pressed it hard you might burst it. We put some vinegar in another jar and very gently placed the egg in the jar.

The egg on the left still has some residue of the shell. You can see the membrane of the egg on the right.

Day 5 Today we went back to see the egg. It didn’t look any different to yesterday when we changed the vinegar. The shell has disintegrated and you could see the white membrane underneath. We could see that the egg was now almost as wide as the jar. We will need to change the jar or it will get stuck. We could still see a few bubbles 

We wanted to test the strength of the membrane so we dropped the egg 30 centimeters.

Lab report day 6

This is the last day of our experiment. The egg was spongy so we decided to see what would happen if we dropped it. The egg looked milky white because its shell had gone and much of the vinegar had evaporated. We took it our and cleaned it. We got a metre ruler and put it standing on its end. We lifted the egg 30cm from the table and then dropped it. It burst and the yolk was on the table and the membrane looked like a popped balloon.

The yolk is still intact and the membrane looks like a popped balloon.