Question

sara is making an omelet. she cracks open 6 eggs and places them in a bowl. she adds some milk, salt, and pepper to the eggs and mixes them together with a whisk. next, she takes half of a green pepper and cuts it up into small pieces. she also cuts up some ham and onion. then, sara sprays her pan with cooking spray and then pours in the egg mixture. she lets this cook a little while until it becomes firm. now she adds the green pepper, ham, onion, and some cheese. she then folds half of the eggs over the top to make a half - moon shape. she lets it heat a while longer until the cheese melts and the edges turn brown.

identify all of the physical changes that take place during the making of the omelet. (choose 3)

a cutting pepper
b cutting onion
c cooking eggs
d mixing eggs
e edges turn brown

Explanation:

1. Cutting pepper (A): Cutting the pepper only changes its size and shape, no new substance is formed, so it's a physical change.
2. Cutting onion (B): Similar to cutting pepper, cutting onion just alters its physical form (size/shape) without creating a new chemical substance, so it's a physical change.
3. Mixing eggs (D): Mixing the eggs with milk, salt, and pepper is a physical combination; the substances retain their chemical identities, so it's a physical change.

• Cooking eggs (C) involves a chemical change (denaturation of proteins), and edges turning brown (E) is likely a chemical change (like Maillard reaction), so they are not physical changes.

Answer:

A. cutting pepper, B. cutting onion, D. mixing eggs