NTA Abhyas NEET2020ChemistryElectrochemistryPractice
How long (approximate) should water be electrolysed by passing through 100 amperes current so that the oxygen released can completely burn 27.66 g of diborane? (Atomic weight of B = 10.8 u)
Options
- A1.6 hours
- B6.4 hours
- C0.8 hours
- D3.2 hours
Correct answer
D. 3.2 hours
Step-by-step solution
B 2 H 6 + 3 O 2 → B 2 O 3 + 3 H 2 O According to balanced equation 27.66 g B 2 H 6 i.e. 1 mole B 2 H 6 requires 3 mole of O 2 . Now this oxygen is produced by electrolysis of water as follows 2 H 2 O → 4 F 2 H 2 + O 2 As 1 mole O 2 is produced by 4 F charge So 3 mole O 2 will be produced by 12 F charge So now on applying Q = It 12 × 96500 C = 100 × t ( s ) t = 12 × 96500 100 × 3600 hours t = 3.2 hours