Question

Imagine you are a chef. You must make a lunch that does not involve any chemical changes in the preparation. Name three foods or drinks you will serve, and describe what physical changes you will use to prepare them.

Answer 1

So,

First of all, let's remember what physical and chemical changes are.

A physical change occurs when there's changes in the size or shape of matter. Changes of state, for example, from solid to liquid or from liquid to gas, are also physical changes. In this kind of change, the composition of the matter doesn't change.

A chemical change occurs when a substance combines with another to form a new substance, and the composition of the matter changes.

Now that we know what these changes are, we could give some examples of a physical change in cooking, for example:

1. Suppose we want to serve a freezed drink, like a popsicle. For this, we could freeze a fruit juice. This is a physical change because the composition of the juice changes from liquid to solid.

2. Suppose we want to serve pasta. We need to boil the pasta to make it soft, which is a physical change clearly.

3. Suppose we want to serve meat but this is freezed, so, we need to thaw it to start cooking, which is a physical change.