NTA Abhyas NEET2020ChemistryElectrochemistryPractice
How long a current of 3 amperes has to be passed through a solution of A g N O 3 to coat a metal surface of 80 c m 2 with a 0.005 mm thick layer. (Density of Ag is 10.5 g c m - 3 ).
Options
- A125.09 sec
- B1.251 sec
- C12.51 sec
- D12.61 sec
Correct answer
A. 125.09 sec
Step-by-step solution
Weight of Ag deposited = Volume × density = ( A r e a × t h i c k n e s s ) × d e n s i t y = 80 × 5 × 1 0 - 11 × 10.5 = 0.42 g t = W × F E × i = 0.42 × 96500 108 × 3 = 125.09 sec.