Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Electrochemistry question

2022 · 26 Jun · Shift 1 · Q4
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /JEE Main
  3. /Chemistry
  4. /Electrochemistry
  5. /2022 · 26 Jun · Shift 1 · Q4

Electrochemistry question

2022 · 26 Jun · Shift 1 · Q4

JEE MainChemistryElectrochemistryMCQ+4 / −1

The (∂E∂T)P{\left( {{{\partial E} \over {\partial T}}} \right)_P}(∂T∂E​)P​ of different types of half cells are as follows:

A B C D
1×10−41 \times {10^{ - 4}}1×10−4 2×10−42 \times {10^{ - 4}}2×10−4 0.1×10−40.1 \times {10^{ - 4}}0.1×10−4 0.2×10−40.2 \times {10^{ - 4}}0.2×10−4

(Where E is the electromotive force)

Which of the above half cells would be preferred to be used as reference electrode?

  1. A
    A
  2. B
    B
  3. C
    C
  4. D
    D
View written solutionFree

Correct answer: C

  1. Condition for a good reference electrode

A reference electrode should have a stable electrode potential, i.e. its potential should change as little as possible with external conditions.

Here, the temperature dependence is given by

(∂E∂T)P\left(\frac{\partial E}{\partial T}\right)_P(∂T∂E​)P​

So, for a good reference electrode, this value should be minimum in magnitude.

  1. Given values

For the four half-cells:

  • A: 1×10−41 \times 10^{-4}1×10−4
  • B: 2×10−42 \times 10^{-4}2×10−4
  • C: 0.1×10−40.1 \times 10^{-4}0.1×10−4
  • D: 0.2×10−40.2 \times 10^{-4}0.2×10−4
  1. Compare the values

The smallest value is

0.1×10−40.1 \times 10^{-4}0.1×10−4

which corresponds to half-cell C.

  1. Conclusion

Since the reference electrode should have the least variation of emf with temperature, C is preferred.

Derived answer: C

PreviousNext

More from Electrochemistry

  • Cu(s) + Sn2+ (0.001M) → Cu2+ (0.01M) + Sn(s) The Gibbs free energy change for the above reaction at 298 K is x × 10 − 1 kJ mol − 1. The value of x is ​. [nearest integer] [Given : ECu2+/CuΘ​=0.34V…2022 · Numerical
  • Given below are two statements : Statement I : For KI, molar conductivity increases steeply with dilution Statement II : For carbonic acid, molar conductivity increases slowly with dilution In the light of the above statements, choose the…2022 · MCQ
  • The limiting molar conductivities of NaI, NaNO3​ and AgNO3​ are 12.7, 12.0 and 13.3 mS m2 mol − 1, respectively (all at 25 ∘ C). The limiting molar conductivity of AgI at this temperature is ​ mS…2022 · Numerical
  • For the reaction taking place in the cell : Pt (s)| H2​ (g)|H+(aq) || Ag+(aq) |Ag (s) E cello​= + 0.5332 V. The value of Δ fG ∘ is ​ kJ mol − 1. (in nearest integer)2022 · Numerical
  • In 3d series, the metal having the highest M2+/M standard electrode potential is :2022 · MCQ
  • Match List - I with List - II. Choose the correct answer from the options given below: Includes table2022 · MCQ
  • The quantity of electricity in Faraday needed to reduce 1 mol of Cr2O 72−​ to Cr3+ is ​.2022 · Numerical
  • For the given reactions Sn2+ + 2e −→ Sn Sn4+ + 4e −→ Sn the electrode potentials are ; ESn2+/Sno​=−0.140 V and ESn4+/Sno​=+0.010 V. The magnitude of standard electrode potential for Sn4+/Sn2+…2022 · Numerical