AP EAMCET202422 May 2024Morning ShiftChemistryElectrochemistryActual
In which of the following Galvanic cells emf is maximum? (Given: E _ Mg ²⁺ Mg ^0=-2.36 ~V and E _ Cl ₂ 2 Cl ⁻ ^0=+1.36 ~V )
Options
- AMg | Mg ²⁺(1 M ) | 2 Cl ⁻(1 M ) | Cl ₂(1 ~atm ), Pt
- BMg | Mg ²⁺(0.01 M ) | 2 Cl ⁻(1 M ) | Cl ₂(1 ~atm ), Pt
- CMg | Mg ²⁺(1 M ) | 2 Cl ⁻(0.01 M ) | Cl ₂(1 ~atm ), Pt
- DMg | Mg ²⁺(0.01 M ) | 2 Cl ⁻(0.01 M ) | Cl ₂(1 ~atm ), Pt
Correct answer
D. Mg | Mg ²⁺(0.01 M ) | 2 Cl ⁻(0.01 M ) | Cl ₂(1 ~atm ), Pt
Step-by-step solution
gathered Mg Mg ²⁺+2 e ⁻ Cl ₂ +2 e ⁻ 2 Cl ⁻ Mg + Cl ₂ Mg ²⁺ 2 Cl ⁻ gathered (a) aligned & E _ cell = E ^ - RT nF [ MgH ₂ ] [ Cl ⁻ ]^2 & E _ cell =3.72- RT nF (1)^2 1 & E _ cell =3.72- RT nF 1 aligned (b) aligned & E _ cell = E ^ - RT nF (1)^2 10⁻² & = E ^ +2 RT nF 10 aligned (c) aligned & E _ cell = E ^ - RT nF (10⁻² )^2 1 & = E ^ +4 RT nF 10 aligned (d) aligned & E _ cell = E ^ - RT nf (10⁻² )^2 10⁻² & = E ^ =6 RT nF 10 aligned So 'd' option have highest emf.