A steady current of 1.5 A flows through a copper voltameter for 10 min. If the electrochemical equivalent of copper is 30 x 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
Apply first law of electrolysis during deposition fo charge on an electrode through electrolysis.
If m is the mass of 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 directly proportional q
m =zq
where z is a constant of proportionality and is called electrochemical equivalent (ECE) of the the substance.
If an electric current I flows through the electrolytem, then
q = It
m= zit
Here, i = 1.5 A, t= 10 min= 10 x 60 s
z = 30 x 10-5 g C-1
Hence, the mass of copper deposited on the electronde
m= 30 x 10-5 x 1.5 x 10 x 60
= 27 x 10-2 = 0.27 g
