A brass cylinder is composed of copper (8.96 g/cm³)and zinc (7.14 g/cm³).It is 62.1% copper by mass.What is the cylinder's density?

Question

Quizplus · Accepted Answer

Since the cylinder is 62.1% copper by mass, we can assume that it is also 62.1% copper by volume, since copper and zinc have the same density in this problem. Therefore, the density of the cylinder can be calculated using the following equation:

density = (0.621)(8.96 g/cm3) + (0.379)(7.14 g/cm3)
density = 5.56976 g/cm3 + 2.71206 g/cm3
density = 8.28182 g/cm3

Rounding to the nearest hundredth gives a final answer of 8.27 g/cm3, which is closest to choice B.

A Brass Cylinder Is Composed of Copper (8