How many Coulombs of electricity are required for the oxidation of one mole of water to dioxygen?

• 9.65 × 10⁴ C

• 1.93 × 10⁴ C

• 1.93 × 10⁵ C

• 19.3 × 10⁵ C

By passing electric current, NaClO₃ is converted in to NaClO₄ according to the following equation

NaClO₃ + H₂O → NaClO₄ + H₂

How many moles of NaClO₄ will be formed when three Faradays of charges is passed through NaClO₃ ?

• 3.0

• 1.5

• 0.75

• 1.0

The final products formed on the addition of KI to copper sulphate solution are :

• K₂SO₄.CuI₂ and I₂

• K₂SO₄.Cu₂I₂ and I₂

• K₂SO₄ and Cu₂O

• K₂SO₄.CuO and I₂

In the electrolysis of aqueous sodium chloride solution, which of the half cell reaction will occur at anode?

• 2H₂O (l) → O₂ + 4H⁺ +4e^-, E${}_{\mathrm{cell}}^{°}= +1.23\mathrm{V}$

• 2H⁺(aq) + e^- → 1/2H_{2,${\mathrm{E}}_{\mathrm{cell}}^{°}= -0.00\mathrm{V}$}

• Na⁺ (aq) + e^- → Na(s) E${}_{\mathrm{cell}}^{°}= -2.71\mathrm{V}$

• Cl^-(aq) → 1/2 Cl₂ + e^-, E${}_{\mathrm{cell}}^{°}=1.36\mathrm{V}$

The standard reduction potential at 298K the following half cell reaction.

Zn²⁺(aq) + 2e^- → Zn(s); E°= -0.762V

Cr³⁺(aq) + 3e^- → Cr(s); E°= -0.740V

2H⁺(aq) + 2e^- → H₂(g); E°= 0.0V

F₂(g) + 2e^- → 2F^-(aq); E°= 2.87V

Which of the following is strongest reducing agent?

• Zn(s)

• Cr(s)

• H₂(g)

• F₂(g)

Which of the following ions can be replaced by H⁺ ions when H₂ gas is bubbled through the solutions containing these ions ?

• Li

• Ba²⁺

• Cu²⁺

• Be²⁺

The emf of the cell $\left({\mathrm{E}}_{{\mathrm{Zn}}^{2+}/ \mathrm{Zn}} = -0.76 \mathrm{V}\right)$

Zn/ Zn²⁺ (1M) || Cu²⁺ (1M) Cu

$\left({\mathrm{E}}_{{\mathrm{Cu}}^{2+}/ \mathrm{Cu}} = +0.34 \mathrm{V}\right)$ will be

• +1.10 V

• -1.10 V

• +0.42 V

• -0.42 V

218.

For the redox reaction

Zn (s) + Cu²⁺ (0.1 M) → Zn²⁺ (1 M) + Cu (s)

taking place in a cell, E${}_{\mathrm{cell}}^{°}$ is 1.10 V. E_cell for the cell will be $\left(2.303 \frac{\mathrm{RT}}{\mathrm{F}} = 0.0591\right)$

• 2.14 V

• 1.80 V

• 1.07 V

• 0.82 V

The highest electrical conductivity of the following aqueous solutions is of

• 0.1 M difluoroacetic acid

• 0.1 M fluoroacetic acid

• 0.1 M chloroacetic acid

• 0.1 M acetic acid

Aluminium oxide may be electrolysed at 1000°C to furnish aluminium metal (atomic mass = 27 amu; 1 F = 96,500 C). The cathode reaction is

Al³⁺ + 3e^- → Al⁰

To prepare 5.12 kg of aluminium metal by this method would require

• 5.49 × 10¹ C of electricity

• 5.49 × 10⁴ C of electricity

• 1.83 × 10⁷ C of electricity

• 5.49 × 10⁷ C of electricity