Question

Calculate the volume of H2 gas (25 Celsius and 760 mm Hg) that will collect at the cathode when an aqueous solution of Na2SO4 is electrolytes for 90 minutes with a 12amp current.

Answer 1

Coulombs = amp x seconds = 12 x 90 x 60 = approx 65,000
2H^+ + 2e ==> H2
96,500 coulombs will release 1/2 mol H2.
Now PV = nRT =? You have P = 1 atmosphere.
V = ?
n = 1/2
R you know
T in kelvin.
Solve for V in liters.
Post your work if you get stuck.

Answer 2

Wouldn't I need to divide by 2 mol e^- to convert to moles of H^+?

Answer 3

Hey ryan thats what I did but I thought it was right? I'll show you tomorrow in lab.

Answer 4

Student