Question

3
.
The given figure shows the process of purification of
copper. A thin plate of pure copper and a thick rod
of impure copper are used as electrodes along with
copper sulphate solution. Copper from impure rod is
sought to be transferred to thin copper plate.
Battery
Thin plate
of pure
copper
11
III
Thick rod of
impure copper
Copper sulphate
solution​

Answer 1

Answer:

because, Cu+2 is move from anod to cathod

so, pure Cu is connected to cathod and impure Cu is connected to anod.

Answer 2

Answer:

The thick rod of impure copper plate is to be attached to the positive terminal of the battery because when electric current is passed through the copper sulphate solution, it gets dissociated into copper and sulphate. The free copper, being positively charged, gets drawn to the negative terminal of the battery and gets deposited on it. On the other hand the loss of copper from the solution is regained from the impure copper rod which is attached to the positive terminal of the battery.