# Question ac924

Jan 16, 2017

Approx. $0.029 \cdot m o l$ of benzene.................And the number of moles is equal to the number of benzene molecules.

#### Explanation:

We need to find the molar quantity of benzene, and thus we simply perform the operation:

$\text{Mass"/"Molar mass of benzene}$ to give an answer in moles, $=$

$\frac{2.24 \cdot \cancel{g}}{6 \times 12.011 \cdot \cancel{g} \cdot m o {l}^{-} 1 + 6 \times 1.00794 \cdot \cancel{g} \cdot m o {l}^{-} 1}$

$= 0.0287 \cdot m o l$.

Note that this is dimensionally consistent, because, 1/("mol"^-1)=1/(1/"mol")="mol"#

So there are $0.0287 \cdot m o l$ of benzene $\text{molecules}$.

And since $1 \cdot m o l \equiv \text{Avogadro's number of molecules}$ $=$ $6.022 \times {10}^{23} \cdot m o {l}^{-} 1$

And $= 0.0287 \cdot m o l \cdot \text{benzene molecules"xx6.022xx10^23*mol^-1="How many benzene molecules?}$

And $\text{how many atoms?}$, $= 0.0287 \cdot m o l \times 12 \cdot \text{atoms"*mol^-1xx6.022xx10^23*mol^-1="How many atoms?}$

Why did I need to multiply the molar quantity by $\text{12 atoms?}$