# How is molar mass of an element used to convert from number of mass in grams?

Dec 3, 2016

$\text{Number of moles}$ $=$ "Mass (g)"/("Molar mass "("g"*"mol"^-1)

#### Explanation:

The given quotient is certainly sound dimensionally, in that $\frac{g}{g \cdot m o {l}^{-} 1}$ reduces to $\frac{1}{m o {l}^{-} 1}$ $=$ $m o l$.

And thus a $12 \cdot g$ mass of carbon $\equiv \frac{12 \cdot g}{12 \cdot g \cdot m o {l}^{-} 1} = 1 \cdot m o l .$

Are you happy with this?

If you are how many moles does a $32 \cdot g$ mass of elemental oxygen, and a $71 \cdot g$ mass of elemental chlorine represent?