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Electrochemistry

Question
CBSEENCH12006035

When a current of 0.75 A is passed through a CuSO4 solution for 25 min, .36 g of copper is deposited at the cathode. Calculate the atomic mass of copper.

Solution

Time  = 25 min  = 25 x 60 sec
Current     = 0.75 A
Cu2++2e-      Cu
Electricity passed  = 25 x 60 x 0.75  = 1125 C of electricity deposit copper  = 0.369 g. 2 x 96500 C
of electricity will deposit copper.
M= ZxIxT

= 2 × 96500 × 0.369 1125
Atomic mass of copper = 63.3 u.