Charge required to liberate hydrogen from water

The process of liberating hydrogen from acidified water is an electrolytic process. It involves the passage of electricity through the water to break down the water molecules into hydrogen and oxygen. The amount of charge required to liberate a certain volume of hydrogen can be calculated using Faraday's laws of electrolysis.

Faraday's laws state that the amount of chemical change produced by an electric current is proportional to the quantity of electricity passed through the solution. The quantity of electricity is measured in Coulombs (C) and is given by the formula:

Q = I x t

where Q is the quantity of electricity, I is the current in amperes (A), and t is the time in seconds (s).

The charge required to liberate hydrogen from water can be calculated as follows:

1. Write the balanced chemical equation for the electrolysis of water:

2H2O(l) → 2H2(g) + O2(g)

2. Calculate the number of moles of hydrogen gas produced:

n(H2) = V(H2)/V(molar) = 0.112/22.4 = 0.005 mol

where V(H2) is the volume of hydrogen gas produced (112 ml), V(molar) is the molar volume of gas at standard temperature and pressure (22.4 L/mol).

3. Use the stoichiometry of the balanced chemical equation to find the number of moles of electrons required to produce the hydrogen gas:

4 e- + 2H2O(l) → 2H2(g) + O2(g)

n(e-) = 4 x n(H2) = 0.02 mol

4. Calculate the charge required to produce the required number of electrons:

Q = n(e-) x F

where F is the Faraday constant, which is equal to 96,500 C/mol.

Q = 0.02 x 96,500 = 1,930 C

Therefore, the charge required to liberate 112 ml of hydrogen from acidified water is 1,930 C, which is closest to option C (965 C).