Homework - Chemistry Chapter 13 Heat of Precipitation

An experiment was carried out to determine the heat of precipitation of barium sulphate. 50 cm cube of 1.0 mol dm cube potassium sulphate solution and 50 cm cube of 1.0 mol dm cube barium chloride solution are pured into two separated plastic beakers. The initial temperatures of the solutions are recorded. Then, potassium shulphate solution is quickly poured into the plastic beacker containing barium chloride solution. The mixture is stirred slowly. The results are shown as below

Initial temperature of K2SO4 = 29.5 C
Initial temperature of BaCl2 = 29.5 C

Maximum temperature of the mixture = 34.5 C

a) What is meant by heat of precipitation

b) Write an ionic equation for the reaction

c) State an observation for the experiment

d) i) Calculate the heat chang in the experiment in joules [ Specific heat capacity of solution = 4.2 J/g/C. Density of solution = 1.0 g/cm cube

d) ii) Calculate the number of moles of barium sulphate formed

d) iii) the heat of precipitation of barium shulphate in kJ mol-1

e) Draw the enery profile diagram for the precipitation of barium sulphate