CBSE 2023 · Region 1 · Set 3 · Q20 · 2 marks
Calculate $\displaystyle \Delta_{\mathrm{r}} \mathrm{G}^{\circ}$ for the cell reaction at $\displaystyle 25$°C: \[\mathrm{Zn}\left|\mathrm{Zn}^{2+} \| \mathrm{Cd}^{2+}\right| \mathrm{Cd} \] Given that: \[\begin{aligned} & \mathrm{E}_{\mathrm{Zn}^{2+} / \mathrm{Zn}}^{\circ}=-0.76 \mathrm{~V}, \quad \mathrm{E}_{\mathrm{Cd}^{2+} / \mathrm{Cd}}^{\circ}=0.40 \mathrm{~V} \\ & 1 \mathrm{~F}=96500 \mathrm{C} \mathrm{~mol}^{-1} \end{aligned} \]The electrical resistance of a column of $\displaystyle 0.05 \mathrm{~mol} \mathrm{~L}^{-1} \mathrm{NaOH}$ solution of diameter $\displaystyle 1$ cm and length $\displaystyle 50$ cm is $\displaystyle 5.55 \times 10^{3}$ ohm. Calculate the conductivity.
Calculate $\displaystyle \Delta_{\mathrm{r}} \mathrm{G}^{\circ}$ for the cell reaction at $\displaystyle 25$°C: \[\mathrm{Zn}\left|\mathrm{Zn}^{2+} \| \mathrm{Cd}^{2+}\right| \mathrm{Cd} \] Given that: \[\begin{aligned} & \mathrm{E}_{\mathrm{Zn}^{2+} / \mathrm{Zn}}^{\circ}=-0.76 \mathrm{~V}, \quad \mathrm{E}_{\mathrm{Cd}^{2+} / \mathrm{Cd}}^{\circ}=0.40 \mathrm{~V} \\ & 1 \mathrm{~F}=96500 \mathrm{C} \mathrm{~mol}^{-1} \end{aligned} \]
The electrical resistance of a column of $\displaystyle 0.05 \mathrm{~mol} \mathrm{~L}^{-1} \mathrm{NaOH}$ solution of diameter $\displaystyle 1$ cm and length $\displaystyle 50$ cm is $\displaystyle 5.55 \times 10^{3}$ ohm. Calculate the conductivity.
Marking-scheme solution
(a)
\(\displaystyle \mathrm{E}_{\text {cell }}^{\circ}=0.40-(-0.76)=1.16 \mathrm{~V}\)
ElectrochemistryElectrochemical CellsApplyvery_short_answermedium
More from Electrochemistry
- Kohlrausch gave the following relation for strong electrolytes: Λ m=Λ m^°-A √C Which of the following…2025 · asked 4×
- (i) What should be the signs (positive/negative) for E^° Cell and Δ G^° for a spontaneous redox reaction…2023 · asked 3×
- Batteries and fuel cells are very useful forms of galvanic cell. Any battery or cell that we use as a source…2024 · asked 3×
- (i) Calculate emf of the following cell at 25°C: Zn( s) Zn^2+(0 · 001 M) Cd^2+(0 · 1 M) Cd( s) Given: E Zn^2+…2024 · asked 3×
- In a galvanic cell, chemical energy of a redox reaction is converted into electrical energy, whereas in an…2024 · asked 3×
- (i) For a galvanic cell, the following half reactions are given. Decide, which will remain as reduction…2025 · asked 3×
- Write the cell reaction and calculate the e.m.f. of the following cell at 298 K: ( 3 + 2 = 5 ) Sn(s)…2025 · asked 3×
- Four half reactions I to IV are shown below: I. 2 Cl l^- → Cl 2+2 e^- II. 4 OH^- → O 2+2 H 2 O+2 e^- III.…2023 · asked 3×
CBSE Class 12 Chemistry past-paper question from the 2023board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.