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When 20 `cm^3` of l M sodium hydroxide was mixed with 20 `cm^3` of 1 M hydrochloric acid, the temperature rose by `6.7^0C`. Assuming the density
of the solution is l g/`cm^3`and the specific heat capacity of the solution is 4.2 `Jg^-1k^-1`;
(a) Calculate the molar heat of neutralization;
(b) When the experiment was repeated with 1 M ethanoic acid, the temperature change was found to be lower than that with 1 M hydrochloric acid.
Explain.

Answer Text:
Ethanoic acid is a weak acid hence ionizes partially in water. Some energy is therefore used to ionize it fully hence reducing the heat released during
neutralization.