# How many moles are in 2.1 * 10^23 formula units of NaCl?

Feb 27, 2016

This many $N a C l$ units approximately represents $\frac{1}{3}$ mole of $N a C l$.
If I have $6.022 \times {10}^{23}$ individual items of stuff (any stuff), I have $1$ $m o l$ of stuff by definition. Here, I have $2.1 \times {10}^{23}$ formula units of $N a C l$: i.e.
$\left(2.1 \times {10}^{23} \text{ formula units of NaCl")/(6.022xx10^23" formula units of NaCl } m o {l}^{-} 1\right)$ $=$ ?? $\text{moles}$
How many individual $N {a}^{+}$ and $C {l}^{-}$ ions does this represent?