a) (i) Describe, using the kinetic theory of matter, what happens when potassium chloride dissolves in water.
(ii) Give a reason why the process in (a) (i) is endothermic.                      

 

(b) (i) An underground iron pipe is less likely to corrode if it is bonded at intervals with magnesium rods. Give reasons for this observation.
(ii)  State the stages involved in the rusting of iron.
(iii) State the condition for the rusting of iron in water.                                 

 

(c) (i)  What is a spontaneous reaction?
(ii)  State two conditions that could make a reaction spontaneous.
(iii) Explain briefly why one gramme of sodium reacts more rapidly with water at 250C than one gramme of calcium at the same temperature.
(iv)   Write equations for the reactions in (c)(iii).                                        

(d)   What mass of lead (II) trioxocarbonate (IV) would contain 35.0 g of lead?
[C=12.0, O = 16.0, Pb = 207.0]                                                         

 

(e)  Name the type of intermolecular force present in:

(i)         fluorine;
(ii)        hydrogen fluoride.