A steady current of 1.5 A flows through a copper voltameter for 10 min. If the electrochemical equivalent of copper is 30x 10-5 g C-1 , the mass of copper deposited on the electrode will be
0.40 g
0.50 g
0.67 g
0.27 g
D.
0.27 g
If m is the mass of a substance deposited or liberated at an electrode during electrolysis when a charge q passes through electrolyte, then according to Faraday's first law of electrolysis,
m ∝ q
⇒ m = zq
where z is a constant of proportionality and is called electrochemical equivalent (ECE) of the substance.
If an electric current I flows through the electrolyte, then
q = (I.t)
m = zIt
Here , I = 1.5 A,
t = 10 min = 10 × 60 s
z = 30 × 10-5 gC-1
Hence, mass of copper deposited on the electrode
m = 30 × 10-5 × 1.5 × 10 × 60
= 27 × 10-2
m = 0.27 g
