Chapter 3, Problem 67E

Gather any two of the following items, measure their dimensions, and calculate the number of atoms present in the item.

a. a copper penny (pre-1983), density of copper = $\text{8}{\text{.96 g/cm}}^{\text{3}}$

b. a nickel (assume that the nickel is pure nickel, Ni), density of nickel = $\text{8}{\text{.90 g/cm}}^{\text{3}}$

c. a graphite pencil lead (pure carbon), density of carbon = $\text{2}{\text{.62 g/cm}}^{\text{3}}$

d. a helium balloon (assume that the balloon is approximately spherical; the volume of a sphere is $V\text{=}\left(\frac{4}{3}\right)\pi r^3$, where r is the radius), density of helium gas = 0.0899 g/L