In order to determine the molar heat of neutralization of 1M potassium hydroxide, 200cm³ of 1M hydrochloric acid both at the same temperature were mixed...

In order to determine the molar heat of neutralization of 1M potassium hydroxide, 200cm³ of 1M hydrochloric acid both at the same temperature were mixed and stirred continuously with a thermometer. The temperature of the resulting solution was recorded after every 30 seconds until the highest temperature of the solution was attained.

(a) (i) Why was it necessary to stir the mixture of the two solutions?
(ii) Write an ionic equation for the reaction.

(b) The initial temperature for both solution was 24.5°C and the highest temperature attained by the mixture was 30.9°C. Calculate the
(i) heat change for the reaction.
(Specific heat capacity of the solution is Density of the solution is
The volume of KOH used was 200cm³.
(ii) molar heat of the neutralisation.

(c) If ammonium hydroxide was used instead of potassium hydroxide the heat of neutralization would be different from the one obtained in b(ii) above.
Explain the difference.

(d) Draw an energy level diagram for the reaction between potassium hydroxide and hydrochloric acid.

Answers

(a) (i) To distribute heat uniformly // uniform mixture of reagents.
(ii) Heat evolved when one molar of water is formed from the reaction between H⁺ and OH^- ions.

maurice.mutuku answered the question on September 16, 2019 at 09:45

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