Question

what current in ampere is required to produce 50.0ml of O2 gas measured at STP by electrolysis of water for a period of 3hours?

Answer 1

Answer:

Given : 50ml of O2 gas is measured at STP by electrolysis of water for a period of 3 hrs.

To find : The current in Ampere is required to produced O2 gas.

Solution : we know, 2H₂O ⇒2H₂ + O₂

oxidation no of O in water is -2 and oxidation no of O in oxygen gas is 0. so, change in oxidation no of O is 2. there are two oxygen atoms

so, number of electrons are required to change oxidation no of oxygen = 4e¯

here volume of O2 = 50 ml

no of moles of O2 = 50ml/22400ml = 0.00223 mol.

we need 0.00223 mol × 4e¯ per second.

so, current = total charge × time

= 0.00223 × 6.023 × 10²³ × 1.6 × 10^-19 × 3 × 3600

= 77.36 × 10⁴ A

= 7.736 × 10^5 A (approximately)

Therefore 7.736 × 10^5 Ampere current is required to produce 50 ml of O2 gas.