A-LevelChemistryChemical energeticsMay/June 2012Paper 1 Q141 Mark
Slaked lime, Ca(OH)2, may be made from limestone, CaCO3. On heating in a lime kiln at 1000°C, limestone decomposes as follows. reaction 1 CaCO3(s) → CaO(s) + CO2(g) Water is then reacted with calcium oxide, CaO, as follows. reaction 2 CaO(s) + H2O(l) → Ca(OH)2(s) What are the enthalpy changes of these reactions?
Aendothermic endothermic
Bendothermic exothermic
Cexothermic endothermic
Dexothermic exothermic
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The correct answer is B. This question tests the candidate's understanding of chemical energetics within the Chemistrysyllabus. The examiner's mark scheme requires...
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