Chemistry Paper 1 (Practical) ,May/June 2011  
Questions:       1 2 3 4 5 6   Main
General Comments

Question 6

The following diagram is a set-up for the separation of a mixture of palm oil and water:


  1. (i)         State one physical property of the liquids that would enhance their separation.
    (ii)        Identify X;Y.
    (iii)        Name the apparatus labelled Z.
  2. Name two basic apparatus used in each of the following separation methods:
    fractional distillation;
    paper chromatography;
  3. (i)         What is the colour of phenolphthalein in aqueous ammonium chloride?
    (ii)        State what would be observed on:
               bubbling chlorine through iron (II) chloride solution;
                 passing ethene through bromine water

Part (a) candidates performed well in this question.  Part (b) many candidates could not answer this part correctly probably due to lack of laboraory equipment.  Part (c) was also poorly done by most candidates as they could not state correctly the colour changes as required by the question.

The expected answers are:

(a)(i)    Immisciblility (accept not miscible)
    (ii)   I.    X - palm oil
           II.   Y - water
   (iii)  Z - separating funnel

(b)(i)   fractionating column, liebig condenser, thermometer, source of heat, retort standwith clamp, distillation flask.
    (ii)   glass cover/split cork, tank/boiling tube/beaker, filter paper/plate
   (iii)   evaporating basin/dish/beaker, tripod stand with wire gauze, source of heat/bunsen burner.

(c)(i)   colourless
  (ii)  I .  the green iron  (II) chloride changes to brown
           II.  bromine water being brown changes to colourless/brown colour of bromine water decolorised.


Powered by Sidmach Technologies(Nigeria) Limited .
Copyright © 2015 The West African Examinations Council. All rights reserved.