when the magnitude of the charge Q = I*T
when we have I current = 2.3
and T = 35 min * 60 = 2100 s
by substitution:
∴ Q = 2.3 * 2100
= 4830 C
according to this reaction equation:
Cu2+ + 2e- → Cu
we can see that 1 mol Cu2+ need 2 mol e- to produce Cu
mol of electron e- = Q / faraday's constant
= 4830 / 96485
= 0.05 mol
when 1 mol Cu2+ → 2 mol e-
?? ← 0.05 mol
∴ moles Cu2+ = 0.05 /2 = 0.025 mol
∴ mass Cu2+ = moles Cu2+ * molar mass Cu2+
= 0.025 * 64
= 1.6 g
