Question

Find the number of moles of $HN{O}_3$ in a sample containing ${10}^8$ molecules of $HN{O}_3$.

• A. $1.66\times {10}^{-16}$
• B. ${10}^8$
• C. $1.66\times {10}^{16}$
• D. $6.022\times {10}^{15}$

Answer 1

The correct option is A $1.66\times {10}^{-16}$

$Numberofmoles=\frac{Numberofmolecules}{Avogadronumber}$
$=\frac{{10}^{8}molecules}{6.022\times {10}^{23}molecules/mol}$
$=1.66\times {10}^{-16}$