Answer to Question #197991 in General Chemistry for Riane

Question

A coffee-cup calorimeter initially contains 125 g water at 24.2°C. Potassium bromide (10.5 g), also at 24.2°C, is added to the water, and after the KBr dissolves, the final temperature is 21.1°C. Calculate the enthalpy change for dissolving the salt in J/g and kJ/mol. Assume that the specific heat capacity of the solution is 4.18 J/g °C and that no heat is transferred to the surroundings or to the calorimeter.

Answer 1

Enthalpy change for dissolving the salt;

$\Delta H=167.2J/g$

$\Delta H=19.9kJ/mol$