Question

Al₂O₃ is reduced by electrolysis at low potentials and high currents. If 4.5 x 10⁴ An of current is passed through molten Al₂O₃ for 6h, what mass of aluminium is produced? (Assume 100% current efficiency, at.mass of Al = 27 g mol^-1)

9.0 x 10³ g

8.1 x 10⁴ g

2.4 x 10⁵ g

1.3 x 10⁴ g

Solution

8.1 x 10⁴ g

Al₂O₃ ionises as,
$Al subscript 2 straight O subscript 3 space leftwards harpoon over rightwards harpoon space Al to the power of plus subscript cathode space plus space stack AlO subscript 3 superscript 3 minus end superscript with Anode below At space Cathode Al to the power of 3 plus end exponent space plus space stack 3 straight e to the power of minus with 3 straight F below space rightwards arrow stack space Al with 27 below because space Mass space of space aluminium space deposited space by space 3 space straight F space of space electricity space equals space 27 4.0 space straight x space 10 to the power of 4 space straight x space 6 space straight x space 3600 space straight C space of space electricy space equals space fraction numerator 27 space straight x space 4.0 space straight x space 10 to the power of 4 straight x space 6 space straight x space 3600 over denominator 3 straight F end fraction space equals space fraction numerator 27 space straight x space 4.0 space straight x space 10 to the power of 4 space straight x space 6 space straight x space 3600 over denominator 3 space straight x space 96500 end fraction straight g space equals space 8.1 space straight x space 10 to the power of 4 space straight g$

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The molar conductivity of 0.025 mol L^–1methanoic acid is 46.1 S cm² mol^–1. Calculate its degree of dissociation and dissociation constant. Give λ°(H⁺) = 349.6 S cm²mol^–1 and λ° (HCOO^– ) = 54.6 s cm² mol^–1.

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The molar conductivity of 0.025 mol L^–1methanoic acid is 46.1 S cm² mol^–1. Calculate its degree of dissociation and dissociation constant. Give λ°(H⁺) = 349.6 S cm²mol^–1 and λ° (HCOO^– ) = 54.6 s cm² mol^–1.

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Al2O3 is reduced by electrolysis at low potentials and high currents. If 4.5 x 104 An of current is passed through molten Al2O3 for 6h, what mass of aluminium is produced? (Assume 100% current efficiency, at.mass of Al = 27 g mol-1) 9.0 x 103 g 8.1 x 104 g 2.4 x 105 g 1.3 x 104 g

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Can you store copper sulphate solutions in a Zinc pot?

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Suggest a way to determine the Λ°m value of water.

The molar conductivity of 0.025 mol L–1 methanoic acid is 46.1 S cm2 mol–1. Calculate its degree of dissociation and dissociation constant. Give λ°(H+) = 349.6 S cm2 mol–1 and λ° (HCOO– ) = 54.6 s cm2 mol–1.

If the current of 0.5 ampere flows through a metallic wire for 2 hours, then how many electrons flow through the wire?

Suggest a list of metals that are extracted electrolytically.

Mock Test Series

NCERT Sample Papers

Entrance Exams Preparation

Suggest a way to determine the Λ°_m value of water.

The molar conductivity of 0.025 mol L^–1methanoic acid is 46.1 S cm² mol^–1. Calculate its degree of dissociation and dissociation constant. Give λ°(H⁺) = 349.6 S cm²mol^–1 and λ° (HCOO^– ) = 54.6 s cm² mol^–1.