# How many moles of BaF are there in 41 grams of BaF?

Mar 5, 2016

Do you mean barium fluoride, $B a {F}_{2}$. I presume you do, because there ain't no such beast as $B a F$. There are approx. $0.25$ $m o l$ $B a {F}_{2}$.

#### Explanation:

$\text{Formula mass,}$ $B a {F}_{2}$ $=$ $175.34 \cdot g \cdot m o {l}^{-} 1$. To get the number of moles, simply divide the mass by the molar mass:

$\frac{41.0 \cdot \cancel{g}}{175.34 \cdot \cancel{g} \cdot m o {l}^{-} 1}$ $=$ ?? $m o l$.

Note that we set this up dimensionally, and automatically got the units of $m o l$, which might persuade us that we got it right (for once!).

How many moles of fluoride ion are in this quantity?