Answer:
[tex]1.29 * 10^{24}[/tex] particles of gold
Explanation:
To convert the number of moles of any substance, in this case gold, you need Avogadro's number.
Avogadro's number is always [tex]6.022[/tex] × [tex]10^{23}[/tex]
[tex]2.15[/tex] moles Au × [tex]\frac{6.022*10^{23} particles}{1 mole Au}[/tex] = [tex]1.29 * 10^{24}[/tex] particles of gold