Calcium oxide and water react in an exothermic reaction: CaO(s) + H₂O(l) $\rarr$ Ca(OH) ₂(s) $\Delta$ H°_rxn = -64.8 kJ/mol
How much heat would be liberated when 7.15 g CaO(s) is dropped into a beaker containing 152g H₂O?

Question

Calcium oxide and water react in an exothermic reaction: CaO(s) + H₂O(l)

\rarr

Ca(OH) ₂(s)

\Delta

H°_rxn = -64.8 kJ/mol
How much heat would be liberated when 7.15 g CaO(s) is dropped into a beaker containing 152g H₂O?

Quizplus · Accepted Answer

The molar mass of CaO is approximately 56.08 g/mol. Therefore, 7.15 g of CaO is equivalent to 7.15 g / 56.08 g/mol = 0.1275 mol. Since the reaction releases 64.8 kJ per mole of CaO, the heat liberated is 0.1275 mol * 64.8 kJ/mol = 8.26 kJ.

Calcium Oxide and Water React in an Exothermic Reaction: CaO(s) →\rarr→

Calcium Oxide and Water React in an Exothermic Reaction: CaO(s) $\rarr$