Tag Archive for: dissolution

1- When a solid dissolves in water, heat may be evolved or absorbed. The heat of dissolution (dissolving) can be determined using a coffee cup…

1- When a solid dissolves in water, heat may be evolved or absorbed. The heat of dissolution (dissolving) can be determined using a coffee cup calorimeter. 
In the laboratory a general chemistry student finds that when 9.72 g of CsCl(s) are dissolved in 113.80 g of water, the temperature of the solution drops from 22.28 to 19.87 °C. 
The heat capacity of the calorimeter (sometimes referred to as the calorimeter constant) was determined in a separate experiment to be 1.71 J/°C.
Based on the student’s observation, calculate the enthalpy of dissolution of CsCl(s) in kJ/mol. 
Assume the specific heat of the solution is equal to the specific heat of water.
ΔHdissolution = ___ kJ/mol
2- When a solid dissolves in water, heat may be evolved or absorbed. The heat of dissolution (dissolving) can be determined using a coffee cup calorimeter. 
In the laboratory a general chemistry student finds that when 10.37 g of NaClO4(s) are dissolved in 100.90 g of water, the temperature of the solution drops from 22.45 to 19.23 °C. 
The heat capacity of the calorimeter (sometimes referred to as the calorimeter constant) was determined in a separate experiment to be 1.72 J/°C.
Based on the student’s observation, calculate the enthalpy of dissolution of NaClO4(s) in kJ/mol. 
Assume the specific heat of the solution is equal to the specific heat of water.
ΔHdissolution =  ____ kJ/mol