What is the metal of this solution

Question

When a solution containing M(NO₃)₂ of an unknown metal M is electrolyzed, it takes 74.1 s for a current of 2.00 A to to plate out 0.0737 g of the metal. The metal is

The correct answer is Mo

Answer 1

2.00 amps = 2 coulombs/sec

2.00 C/sec x 74.1 sec x 1 mol e-/96485 C = 0.001536 moles e-

Since M must have lost 2 electrons to become M²⁺ to react with 2 NO₃^-, we find the moles of electrons...

0.001536 mol e- / 2 = 0.000768 moles M

0.0737 g M/0.000768 mol M = 95.96 g/mol and M = Molybdenum (Mo)