The mass density of silver at room temperature is $10.5 \times 10^{3} \mathrm{~kg} / \mathrm{m}^{3}$ and its atomic mass is $108 \mathrm{~g} / \mathrm{mol}$. If we assume there is one free electron per silver atom, what is the free-electron density for silver, in electrons $/ \mathrm{m}^{3}$ ? How does your answer compare to the free-electron density for copper given in Example $25.1 ?$