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Question
Element X is a metal with valency 2. Element Y is a non-metal with valency 3.
(a) Write equations to show how X and Y form ions.
(b) If Y is diatomic gas, write the equation for the direct combination of X and Y to form a compound.
(c) Write two applications of electrolysis in which anode diminish in mass.
(d) If the compound formed between X and Y is melted and an electric current passed through the molten compound, the element X will be obtained at the _____ and the Y at the ________of the electrolytic cell. (Provide the missing words).
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Solution
(a) X → X2+ + 2e-
Y + 3e- → Y3-
(b) 3X + Y2 → X3Y2
(c) (i) Electroplating of metals
(ii) Electrorefining of metals
(d) If the compound formed between X and Y is melted and an electric current passed through the molten compound, the element X will be obtained at the cathode Y at the anode of the electrolytic cell.
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