Chapter 24, Problem 44R

To determine

To calculate: Mass of the bar and mass of gold in the bar.

Answer to Problem 44R

Mass of the bar = $\underset{\_}{12.5\text{ g}}$ .

Mass of gold = $\underset{\_}{11.5\text{ g}}$ .

Explanation of Solution

Given info:

Percentage of copper = $\text{8\%}$

Percentage of gold = $\text{92\%}$

Amount of copper = $\text{1 g}$

Calculation:

Mass of bar is calculated as:

  $\begin{array}{l}\text{Mass of copper = 8\% of mass of bar}\\ \text{1 g = }\frac{\text{8}}{100}\text{ of mass of bar}\\ \text{Mass of bar = }\frac{1\times 100}{8}=12.5\text{ g}\end{array}$

Mass of gold in the bar is calculated as:

  $\begin{array}{l}\text{ 92\% of 12}\text{.5}\\ =\frac{92}{100}\times 12.5\\ =11.5\text{ g}\end{array}$

Conclusion:

Mass of the bar = $\underset{\_}{12.5\text{ g}}$ .

Mass of gold = $\underset{\_}{11.5\text{ g}}$ .