A-LevelChemistryGroup 2Oct/Nov 2015Paper 1 Q51 Mark
Calcium forms an ionic compound with carbon, called calcium carbide. The oxidation number of carbon in calcium carbide is –1. Calcium carbide is readily hydrolysed by water giving two products only. What could be the formulae of calcium carbide and the two products of hydrolysis?
Acalcium carbide: Ca2C, products: CaO and C2H4
Bcalcium carbide: Ca2C, products: Ca(OH)2 and C2H2
Ccalcium carbide: CaC2, products: CaO and C2H4
Dcalcium carbide: CaC2, products: Ca(OH)2 and C2H2
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The correct answer is D. This question tests the candidate's understanding of group 2 within the Chemistrysyllabus. The examiner's mark scheme requires...
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