Question

.War nickels, produced from 1942-1945 are composed of 56% copper, 35% silver and 9% manganese. How many moles of each element are found in a 5.00 g nickel coin?

Answer 1

The moles  of each element  found in a 5.00 g nickel coin is calculated as below

moles =mass/molar mass

calculate the mass of each element  =% composition of element/100 x total mass of  nickel

Mn = 9/100 x5 = 0.45g
Cu=56/100 x5= 2.8 g
Ag= 35/100x5=  1.75 g
moles of each element is therefore=
Mn = 0.45g/54.94 =  8.19 x10^-3 moles

Ag=1.75g/107.87 g/mol = 0.0162 moles

Cu = 2.8 g/63.5 g/mol=0.0441  moles