# Question #c3e3a

Oct 13, 2014

in oder to find the mass of one molecule of $N {O}_{2}$ nitrogen dioxide, which could actually be the polyatomic ion nitrite $N {O}_{2}^{-} 1$, we must convert one molecule to moles and than moles to grams.

molecules $\to$ moles $\to$ grams

Begin with one molecule and convert it to moles by using Avogadro's number $6.02 x {10}^{23}$

1 molecule $N {O}_{2}$ x $\left(\frac{1 m o l}{6.02 x {10}^{23}}\right)$ = $1.66 x {10}^{-} 24$ moles

Now convert the moles to grams by using the molar mass (gfm) of $N {O}_{2}$

N = 14.01 x 1 = 14.01 g ${O}_{2}$ = 16.0 x 2 = 32.0 g
14.01 + 32.0 = 46.01 g

$1.66 x {10}^{-} 24$ moles x $\left(\frac{46.01 g}{1 m o l}\right)$ = $7.64 x {10}^{-} 23$ grams $N {O}_{2}$