Using the following thermochemical data, what is the change in enthalpy for the following reaction?

1 answer:

5 0

In calculating the change in enthalpy in a certain reaction, it is important to remember that it is the sum of the enthapy of formation for the substances involved in the reaction.

CaO(s)+2HCl(aq)→CaCl2(aq)+H2O(l) ΔH= –186kJ
Ca(OH)2(aq) → CaO(s)+H2O(l) ΔH= 65.1 kJ
Ca(OH)2(aq) + 2HCl(aq) → CaCl2(aq) + 2H2O(l) ΔH= -120.9 kJ

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