Answer:
Molar heat of solution of KCl = -17.1965kJ/mol
Explanation:
Given Values:
The temperature change = 0.200 K
Mass of KCl = 6.00 g.
Calorimeter heat capacity = 6.92 kJ/K
Heat absorbed by the calorimeter is calculated
Q=CΔT
Where,
Q = amount of heat.
C= the heat capacity.
ΔT = the change in temperature.
Substitution of the values in the equation above.
Q=6.92kJ/K×0.200K=1.384kJ
Heat released by the solution = Heat absorbed by the calorimeter.
Heat evolved by solution=−Qcalorimeter (heat gained by calorimeter)=−1.384kJ
Now, number of moles of KCl is given by
n=W/M
Where,
n = number of moles.
W = mass of KCl .
M = molar mass of KCl = 74.5513g/mol
Substituting in the above equation above we have.
n=6.00g/74.5513g/mol=0.08048 mol
The enthalpy change of the reaction is given by
ΔHsolution per mole=−1.384kJ/ 0.08048mol
ΔHsolution=−17.1965kJ/mol
Therefore the enthalpy for the solution
-17.1965kJ/mol
molar heat of solution of KCl = -17.1965kJ/mol
