Dry air is essentially a mixture of the following entities: \(\mathrm{N}_{2},
\mathrm{O}_{2}, \mathrm{Ar},\) and \(\mathrm{CO}_{2} .\) The composition of dry
air, in mole percent, is \(78.08 \% \mathrm{N}_{2}, 20.95 \% \mathrm{O}_{2},
0.93 \% \mathrm{Ar}\) and \(0.04 \% \mathrm{CO}_{2}\). (a) What is the mass, in
grams, of a sample of air that contains exactly one mole of the entities? (b)
Dry air also contains other entities in much smaller amounts. For example, the
mole percent of krypton (Kr) is about \(1.14 \times 10^{-4} \% .\) Given that
the density of dry air is about \(1.2 \mathrm{g} / \mathrm{L}\) at room
temperature, what mass of krypton could be obtained from exactly one cubic
meter of dry air?