Set 7 Chemistry [Paper] 2

1 SECTION A (60 Marks) Answer only three questions from this section . 1.(a) State Hess’s law of constant heat summation . (01 mark ) b) .Expla in what is meant by each of the following terms and in each case write an equation to illustrate your answer . (@02 marks ) (i) Lattice energy. (ii) Hydration energy . c) Explain two factors that affect the value of lattice energy of a compound. (03 marks) d) In an experiment to determine lattice energy of anhydrous copper (II) sulphate , 4.0g of anhydrous copper (II) sulphate was added to 50.0g of water and the temperature rose by 8.0 ᵒC.When 4.0g of anhydrous copper (II) sulphate was added to 50.0g of water and the temperature dropped from 24.5ᵒC to 23.6ᵒC.[S.H.C of solution = 4.2J/g/K] Calculate the enth alpy of solution of : (@03 marks ) (i) Anhydrous copper (II) sulphate. (ii) Copper (II) sulphate -5-water. e) State which one of the two copper (II) salts in (d) is more soluble in water and explain your answer. (03 marks ) f) Using a Born-Haber cycle determine the hydration energy of anhydro us copper (II) sulphate. (03 marks ) 2. Both phenol and ethanol contain the same functional group . a) (i) Name one reagent that can be used to distinguish between the two compound s. (01 mark) (ii) State what would be observed if each of the compounds is treated with the reagent you have name d and write the equation for the reaction t hat occurs if any. (03 marks ) (iii)Describe three ways in which the chemistry of phenol is similar to that of ethanol. (03 marks ) (iv) Mention two use of phenol. (02 marks ) 2 b) An aqueous solution of phenol turns m oist blue litmus paper red …