### The Law of Multiple Proportions

The law of multiple proportions states that “If two elements form more than one compound between them, then the ratios of the masses of the second element which combine with a fixed mass of the first element will be ratios of small whole numbers.” Even though this may sound complicated, it is actually very simple, and can be seen through the example of cookies.

First we shall look at a chemical example. CO and CO_{2} are both formed from two elements, so if there is a fixed amount of C, then the ratio of O to O_{2} will be a whole number ratio. In this case it is two to one ratio.

Let’s look at the cookie example. A cookie is made up of a base (the actual cookie), and a certain number of chocolate chips as toppings. In this example, the first and constant element is the cookie base, and the second element is the chocolate chips. There are many forms of cookies, 1 base and 1 chocolate chip, 1 base and 2 chocolate chips, 1 base and 3 chocolate chips, and so on. By the law of multiple proportions, the masses of the chocolate chips will be in a whole number ratio.

### Creative Applications

1. How does the cookie example relate to the law of multiple proportions?

2. Why is the law of multiple proportions important?

3. Would chromate and dichromate follow the law of multiple proportions?