Question

Electrolysis of dilute H2SO4 produces H2 gas at cathode. If the minimum voltage required is 1.24V, how many joules of Energy will be used up to produce 1 kg of H2 gas?

Answer 1

Electrolysis of dilute H₂SO₄ produce H2 gas at cathode. minimum voltage required is 1.24 volts.

To find : Energy in joule will be used up to produce 1 kg of H2 gas.

solution : no of moles of H₂ gas = 1000/2.01568 = 496.11 moles

at cathode : 2H⁺ + 2e¯⇔H₂

here it is clear that 2 moles of electrons are required to produce 1 mole of hydrogen gas.

for producing 496.11 moles of hydrogen gas, 992.22 moles of electrons are needed.

we know, 1 mole of electrons is equivalent to 96485C charges.

so, total charge = 992.22 × 96485 = 95,734,346.7 C

now Energy = charge × voltage

= 95,734,346.7 × 1.24

= 118,710,590 J

= 1.18 × 10^8 J

Therefore the energy will be used up to produced 1 kg of Hydrogen gas is 1.18 × 10^8 J