NTA Abhyas NEET2020ChemistryElectrochemistryPractice
A layer of 0.25 mm thick chromium metal is to be electroplated on the rims of autovehicle with a total area of 32 m 2 from a solution of C r O 4 2 - . What amount of electric current is required for electroplating the rims in 60 sec? The density of chromium metal is 7.2 g/cc.
Options
- A4.9 × 1 0 3 A
- B1.78 × 1 0 3 A
- C5.3 × 1 0 4 A
- D10.69 × 1 0 6 A
Correct answer
D. 10.69 × 1 0 6 A
Step-by-step solution
Volume of coated lay = Area × thickness = 32 × 1 0 4 × 0.025 = 8000 c m 3 Mass of chromium deposited = volume × density = 8000 × 7.2 = 57600 g W = I t E 96500 57600 = I × 60 × ( 52 / 6 ) 96500 I = 10.69 × 1 0 6 amp.