Answer
a. $1.03*10^{-4}\text{ mol caffeine}$
b. $3.77*10^{-3}\text{ moles ethanol}$
c. $3.41*10^{-2}\text{ moles $CO_2$}$
Work Step by Step
a. $0.0200\text{ grams caffeine}*\frac{1\text{ mol caffeine}}{194.1906\text{ grams caffeine}}=1.03*10^{-4}\text{ mol caffeine}$
b. $2.27*10^{21}\text{ molecules ethanol}*\frac{1\text{ mol ethanol}}{6.0221*10^{23}\text{ molecules ethanol}}=3.77*10^{-3}\text{ moles ethanol}$
c. $1.50\text{ grams $CO_2$}*\frac{1\text{ mol $CO_2$}}{44.0095\text{ grams $CO_2$}}=3.41*10^{-2}\text{ moles $CO_2$}$