# If there are 7.44 x 10(23) atoms of gold, how many moles of gold are there?

## Reviewing for a final. Went through some old quizzes to work on stuff I got wrong, and all my teacher did be circle it, and I don't understand what I did wrong.

Dec 16, 2017

$= 1.24 m o l A u$

#### Explanation:

1. Given then $\eta \text{atom } A u = 7.44 \times {10}^{23}$, this value can be translated to $\eta A u$ through molar conversion.
2. Knowing the mole relationship as shown below, is your equivalence statement. This is actually the Avogadro's number $\left({N}_{A}\right)$ also known as mole; thus,
$1 m o l A u = 6.02 x {10}^{23} \left({N}_{A}\right) \text{atoms } A u$
3. From the given equivalence statement, two (2) conversion factors can be derived.
$\frac{1 m o l A u}{6.02 \times {10}^{23} \text{atoms"Au) or (6.02xx10^23"atoms} A u} / \left(1 m o l A u\right)$
4. Choose the right conversion factor making sure that the unwanted unit are cancelled leaving the desired one.
=7.44xx10^23cancel("atoms"Au)xx(1molAu)/(6.02xx10^23cancel("atoms"Au))
$= \frac{7.44 \times {10}^{23} m o l A u}{6.02 \times {10}^{23}}$
$= 1.24 m o l A u$