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Of the following elements, which is the least reactive? a. c b. h c. li d. he

Reacting masses1 calcium carbonate breaks down on heating to produce calcium oxide and carbondioxide gas. caco3 + cao + co2a student heats 15 g of calcium carbonate strongly in a crucible. relative atomic masses (a): ca = 40, c = 12, o = 16.calculate the mass of calcium oxide produced by this reaction.(5 marks)