1. Deduce the total number of atoms and molecules in:
(a) one molecule of methane.
(b) one mole of methane.
(c) \( 1.605 \mathrm{~g} \) of methane.
2. What is the mass of:
(a) One mole of sodium chloride, \( \mathrm{NaCl} \) ?
(b) \( 2.00 \times 10^{-2} \mathrm{~mol} \) of glucose, \( \mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6} \) ?
(c) \( 3.62 \mathrm{~mol} \) of magnesium oxide, \( \mathrm{MgO} \) ?
3. What is the mass of:
(a) \( 6.02 \times 10^{23} \) atoms of sulfur, S?
(b) \( 3.01 \times 10^{22} \) iron(II) ions, \( \mathrm{Fe}^{2+} \) ?
(c) \( 1.204 \times 10^{24} \) molecules of water, \( \mathrm{H}_{2} \mathrm{O} \) ?
4. What amount (in \( \mathrm{mol} \) ) is present in:
(a) \( 100 \mathrm{~g} \) of calcium carbonate, \( \mathrm{CaCO}_{3} \) ?
(b) \( 132 \mathrm{~g} \) of carbon dioxide, \( \mathrm{CO}_{2} \) ?
(c) \( 2.497 \mathrm{~g} \) of copper(II) sulfate pentahydrate, \( \mathrm{CuSO}_{4} \cdot 5 \mathrm{H}_{2} \mathrm{O} \) ?
5. How many atoms are present in:
(a) \( 6.41 \mathrm{~g} \) of sulfur dioxide, \( \mathrm{SO}_{2} \) ?
(b) \( 262.6 \mathrm{~g} \) of xenon, \( \mathrm{Xe} \) ?
(c) \( 3.603 \mathrm{~g} \) of aspirin, \( \mathrm{C}_{9} \mathrm{H}_{8} \mathrm{O}_{4} \) ?
6. Deduce the number of nitrogen atoms in:
(a) \( 5.00 \times 10^{-3} \mathrm{~mol} \) of ammonia, \( \mathrm{NH}_{3} \).
(b) \( 14.01 \mathrm{~g} \) of nitrogen gas, \( \mathrm{N}_{2} \).
(c) \( 4.601 \mathrm{~g} \) of nitrogen dioxide, \( \mathrm{NO}_{2} \).
