Chapter 12, Problem 1CYE

To determine

The grams of gold in 5 billion phones, if one cell phone contains 0.03 g of gold.

Answer to Problem 1CYE

The amount of gold present in 5,000,000,000 cell phones is 150,000,000 g.

Explanation of Solution

The symbol of gold is Au. A cell phone is made up of 0.03 g of gold. There are 5,000,000,000 phones that are made up of gold.

One cell phone has 0.03 g of gold.

There are 5,000,000,000 cell phones and each have 0.03 g of gold.

$\begin{array}{c}1\text{Cell}\text{phone}=0.03g\text{of}\text{gold}\\ 5,000,000,000\text{cell}\text{phones}=5,000,000,000\times 0.03g\text{of}\text{gold}\\ =150,000,000g\text{of}\text{gold}\end{array}$

Conclusion:

Hence, the amount of gold present in 5,000,000,000 cell phones is 150,000,000 g.