How much Coulomb needed to convert 1 mole of MnO₄
into Mn²⁺?

• 482500 C

• 193000 C

• 96500 C

• 36500 C

172.

Aluminium is extracted by the electrolysis of

• alumina

• bauxite

• molten cryolite

• alumina mixed with molten cryolite

Saturated solution of KNO₃ is used to make salt bridge because

• KNO₃ is highly soluble in water

• velocity of K⁺ is greater than that of NO${}_3^{-}$

• Velocity of NO${}_3^{-}$ 1s greater than that of K⁺

• velocity of K⁺ and NO${}_3^{-}$ are almost equal

Which of the following is a highly corrosive salt?

• FeCl₂

• PbCl₂

• Hg₂Cl₂

• HgCl₂

One Faraday of charge passes through solution of AgNO₃ and CuSO₄ connected in series and the concentration of two solutions being in the ratio 1 : 2. The ratio of amount of Ag and Cu deposited on Pt electrode is

• 1079.6354

• 54.3177

• 1079.3177

• 54.6354

On passing 0.5 Faraday of electricity through NaCl, the amount of Cl deposited on cathode is

• 35.5 g

• 17.75 g

• 71 g

• 142 g

For a fuel cell, which statementis correct?

• Hydrogen is oxidised to H₂O at cathode

• Oxygen is reduced to OH^- at anode

• Hydrogen is oxidised to H₂O at anode

• Hydrogen is oxidised to H⁺ at anode

An example for a strong electrolyte is

• urea

• ammonium hydroxide

• sugar

• sodium acetate

2 × 10^-5C charge on Zn²⁺  ions corresponds to

• 2 × 10^-5 mol of Zn²⁺ ions

• 6.22  × 10⁷ Zn²⁺ ions

• 0.64 mg of Zn²⁺ ions

• 1 × 10^-10 mol Zn²⁺ ions.

What is the.standard potential of the Tl³⁺/ Tl electrode?

Tl³⁺ +2e^- → Tl⁺, E°= 1.26V

Tl⁺ +e^- → Tl, E°=-0.336V

• 0.924V

• -0.924 V

• 0.728 V

• -0.728V