Respuesta :
Explanation:
According to mole concept, 1 mole of every substance contains [tex]6.02 \times 10^{23}[/tex] atoms or molecules.
As number of atoms present in given copper are [tex]7.8 \times 10^{21}[/tex] atoms. Therefore, calculate the number of moles present in this copper atom as follows.
No.of moles = [tex]\frac{7.8 \times 10^{21}}{6.02 \times 10^{23}}[/tex]
= [tex]1.29 \times 10^{-2}[/tex]
= 0.0129 mol
Thus, we can conclude that there are 0.0129 moles of copper present in [tex]7.8 \times 10^{21}[/tex] atoms.