Answer
(a) 0.520 mol
(b) 4.1 mol
(c) 0.638 mol
(d) 0.0922 mol
Work Step by Step
We find:
(a) $\text{Number of moles}=\frac{\text{Mass of calcium carbonate}}{\text{Molar mass of calcium carbonate}}$
$=\frac{52.0\,g}{100.0869\,g/mol}=0.520\,mol$
(b) $\text{Mass}=\text{Density}\times\text{Volume}=0.76\,g/mL\times250\,mL=190\,g$
$\text{Number of moles}=\frac{\text{Mass of ethanol}}{\text{Molar mass of ethanol}}=\frac{190\,g}{46.07\,g/mol}=4.1\,mol$
(c) $\text{Number of moles}=\frac{\text{Mass of carbon dioxide}}{\text{Molar mass of carbon dioxide}}=\frac{28.1\,g}{44.01\,g/mol}$
$=0.638\,mol$
(d) $\text{Number of moles}=\frac{\text{Number of molecules}}{\text{Avogadro number}}=\frac{5.55\times10^{22}}{6.022\times10^{23}}mol=0.0922\,mol$
