# A sample of carbon dioxide gas contains 6*10^22 molecules. How many moles of carbon dioxide does this represent?

The answer is $\text{0.1000 mol CO"_2}$.
$\text{1 mol CO"_2=6.022xx10^(23) "molecules CO"_2}$
$6.022 \times {10}^{22} \cancel{\text{molecules CO"_2xx(1 "mol CO"_2)/(6.022xx10^23 cancel"molecules CO"_2)="0.1000 mol CO"_2}}$ rounded to four significant figures