Answer
$5.392*10^{24} \text{ atoms Fe}$
$8.953 \text{ mol Fe}$
Work Step by Step
$500.0 \text{ grams Fe}*\frac{1\text{ mol Fe}}{55.845 \text{ grams Fe}}=8.953 \text{ mol Fe}$
$500.0 \text{ grams Fe}*\frac{1\text{ mol Fe}}{55.845 \text{ grams Fe}}*\frac{6.0221*10^{23} \text{ atoms Fe}}{1\text{ mol Fe}}=5.392*10^{24} \text{ atoms Fe}$