Question

State Faraday’s second law of electrolysis.

Hint:

Remember: \[ \boxed{m \propto E} \] For the same charge: \[ \boxed{\text{Deposited mass} \propto \text{Equivalent mass}} \] Equivalent mass: \[ \boxed{ E=\frac{\text{Molar mass}}{\text{Number of electrons involved}} } \]

Answer 1

Concept: Faraday's laws of electrolysis explain the quantitative relationship between the amount of electricity passed through an electrolyte and the amount of substance deposited at the electrodes. Faraday proposed two laws:

• First law: The mass of a substance deposited is directly proportional to the quantity of electricity passed.

• Second law: The mass deposited depends on the equivalent mass of the substance.

Statement of Faraday's Second Law: According to Faraday's second law of electrolysis, if the same amount of electric charge is passed through different electrolytes, the amount of different substances deposited at the electrodes will be proportional to their equivalent masses. The equivalent mass is given by: \[ \boxed{ \text{Equivalent mass}=\frac{\text{Atomic mass or molecular mass}}{\text{Valency}} } \] Therefore, \[ m \propto E \] or, \[ \boxed{ \frac{m_1}{m_2}=\frac{E_1}{E_2} } \] This means that substances with higher equivalent masses require more charge for deposition of the same amount.

Final Answer: Faraday’s second law of electrolysis states that when the same quantity of electricity is passed through different electrolytes, the masses of substances deposited are directly proportional to their equivalent masses. \[ \boxed{ \frac{m_1}{m_2}=\frac{E_1}{E_2} } \]