What is potential of platinum wire dipped into a solution of 0.1 M in Sn²⁺ and 0.01 M in Sn⁴⁺ ?

• E°

• E° + 0.059

• E° + $\frac{0.059}{2}$

• E° - 0.059

Zn(s) | Zn²⁺(aq)|| Cu²⁺(aq) | Cu(s) is :

(anode)                        (cathode)

• Weston cell

• Daniel cell

• Faraday cell

• Standard cell

Copper sulphate solution does not react with

• Zinc

• Iron

• Silver

• All of these

When 1 F of electricity is passed through acidulated water, O₂ evolved is

• 11.2 dm³

• 5.6 dm³

• 22.4 dm³

• 1.0 dm³

Standard electrode potential of cell H₂ | H⁺||Ag⁺| Ag is

• 0.8 V

• -0.8 V

• -1.2 V

• 1.2 V

The oxidation potential values of A, B, C and D are -0.03 V, +0.108 V, -0.07 V and +0.1 V respectively. The non-spontaneous cell reaction takes place between

• A and B

• Band D

• D and A

• B and C

Na is used in reduction of Zn salt because

• E°_{Zn (oxi)} > E°_{Na (oxi)}

• E°_{Zn (red)} > E°_{Na (red)}

• E°_{Zn (oxi)} < E°_{Na (oxi)}

• both (a) and (b)

118.

Reduction potentials of A, B, C and D are 0.8 V, 0.79 V, 0.34 V and -2.37 V respectively. Which element displaces all the other three elements?

• B

• A

• D

• C

During the electrolytic reduction of alumina, the reaction at cathode is

• 2H₂O → O₂ + 4H⁺ + 4e^-

• 3F^- → 3F + 3e^-

• Al³⁺ + 3e^- → Al

• 2H⁺ + 2e^- → H₂

One ampere of current is passed for 9650 seconds through molten AlCl₃. What is the weight in grams of Al deposited at cathode? (atomic weight of Al = 27)

• 0.9

• 9.0

• 0.09

• 90.0