1 My moms chocolate chip cookie recipe calls for an 10 oz ba

1. My mom’s chocolate chip cookie recipe calls for an 10 oz. bag of chocolate chips. If the recipe makes 26 cookies and the whole batch weighs 114 oz.

a. What is the mass percent of chocolate in a single cookie?

b. How many parts per million (ppm) and parts per billion (ppb) of non-chocolate is in each cookie? (Assume I didn’t eat any chips while baking.)

Solution

a) Mass of Chocolate Chips = 10 oz

Mass of the whole batch = 114 oz

Mass percent of chocolate in a single cookie = Mass of Chocolate chips/Mass of the whole batch

=> 10/114 * 100

=> 1000/114

=> 8.7719%

b) Non-cholate in each cookie = 114 - 10 = 104 oz/26 = 4 oz

Chocolate in each cookie = 10/26 = 0.3846 oz

ppm = 4/4.3846 = 912283 parts per million and 912283902 parts per billion