Answer:
mass of Zn = 77.0 g
Explanation:
In the sample you have the same moles of Zn and Ga.
The formula for moles is:
[tex]Mass = moles*MM \\[/tex]
Where MM: Molar Mass or Atomic Mass for elements
AM(Ga) = 69.723 amu
AM(Zn) = 65.38 amu
moles of Ga = [tex]\frac{Mass}{AM} = \frac{82.1 g}{69.723 amu} = 1.178 mole[/tex]
mass of Zn = [tex]moles*AM=1.178 mole*65.38amu = 77.0 g[/tex]
