Exams › JEE Main › Chemistry

For the cell reaction Zn(s) + Ni2+(a = 0.1) -> Zn2+(a = 1.0) + Ni(s), the measured emf at 298 K is 0.5105 V. What is the standard emf (E_cell^o) of the cell?

1. -0.5105 V
2. 0.5400 V
3. 0.4810 V
4. 0.5696 V

Correct answer: 0.5400 V

Solution

Using Nernst, E = E^o - (0.0591/n) log Q. Here Q = 10 (log Q = 1), so E^o = E + (0.0591/2)*1 = 0.5105 + 0.02955 = 0.5400 V.

Related JEE Main Chemistry questions

• During electrolysis of an aqueous solution of dipotassium succinate, which gas is evolved at the electrodes?
• Which expression gives the equivalent conductance at infinite dilution of Al2(SO4)3, if Λ°Al3+ and Λ°SO4²− denote the equivalent conductances at infinite dilution of the corresponding ions?
• The standard emf of a Daniell cell is 1.10 V. What is the greatest amount of electrical work that can be extracted from this cell?
• During the recharging of a lead storage battery, which reaction takes place at the cathode?
• The limiting molar ionic conductivities of the ions X2+ and Y2− are 57 and 73, respectively. What will be the molar conductivity of the electrolyte formed by these ions?
• According to Kohlrausch’s law, at what condition does each ion contribute a fixed amount to the conductance of an electrolyte, irrespective of the other ion present?

⚔️ Practice JEE Main Chemistry free + battle 1v1 →