## Chemistry: Atoms First (2nd Edition)

a. $$3.54 \times 10^{22} \space molecules$$ b. $$1.88 \times 10^{22} \space molecules$$ c. $$2.39 \times 10^{21} \space molecules$$
a. - Using the molar mass as a conversion factor, find the amount in moles: $$1.00 \space g \times \frac{1 \space mole}{ 17.03 \space g} = 0.0587\underline{2} \space mole$$ $$0.0587\underline{2} \space mole \space \times \frac{6.02 \times 10^{23} \space molecules }{1 \space mole} = 3.54 \times 10^{22} \space molecules$$ b. - Using the molar mass as a conversion factor, find the amount in moles: $$1.00 \space g \times \frac{1 \space mole}{ 32.05 \space g} = 0.0312 \space mole$$ $$0.0312 \space mole \space \times \frac{6.02 \times 10^{23} \space molecules }{1 \space mole} = 1.88 \times 10^{22} \space molecules$$ c. - Using the molar mass as a conversion factor, find the amount in moles: $$1.00 \space g \times \frac{1 \space mole}{ 252.08 \space g} = 0.00397 \space mole$$ $$0.00397 \space mole \space \times \frac{6.02 \times 10^{23} \space molecules }{1 \space mole} = 2.39 \times 10^{21} \space molecules$$