You are provided with: - Solution B1 containing 3.15g of a dibasic acid represented as H2A dissolved to make 250cm³ of a solution. - Solution B2, 0.2M sodium hydroxide. - Phenolphthalein indicator.
You are required to:
(i) Titrate solution B₁ against solution B₂. (ii) Determine the molecular mass of the organic acid.

Procedure:
Fill the burette with sodium B₁. Add 1 to 2 drops of phenolphthalein indicator into the solution in the conical flask and then titrate with solution B₁. Pipette 25.0cm³ of solution B₂ sodium hydroxide into a conical flask.
Record your results in the table 1 below.

TABLE 1

(4mks)
(i) Calculate the average volume of solution B1 used. (Show your working clearly).(1mk)
(ii) Write an equation for the reaction between the acid H₂A and solution hydroxide.(1mk)
(c) Calculate:-
(i) The concentration of the acid solution B₁ in moles per litre. (2mks)
(ii) The concentration of acid B₁ in grams per litre. (1mk)

(iii) The relative molecular mass of the acid B₁. (1mk)
(d) Given that the formula of the acid is H₂A.XH₂O. Calculate the value of X.
(H = 1.0, O = 16.0, A = 88.0). (2mks)

You are provided with:-
- Acid D, labeled solution D. -

2.0M sodium hydroxide, solution G.

You are required to:-

Determine the:-
(i) reaction ratio between sodium hydroxide and acid D/
(ii) molar heat of neutralization of acid D with the alkali sodium hydroxide (solution G).

Procedure:
Fill a clean burette with solution D. Place 5cm³ of solution D into a 100ml beaker. Measure
the initial temperature of solution D in the beaker and record it in table 2. Using a 10ml or a
50ml measuring cylinder, measure 25cm³ of solution G. Add it to solution D in the beaker
and immediately stir the mixture gently with the thermometer. Record the maximum
temperature reached in table 2. Repeat the experiment with other sets of volumes of
solution D and G and complete the table

TABLE 2

(a) On the grid provided, plot a graph of ΔT (vertical axis) against the volume of
solution D. (3mks)

(b) From the graph, determine the volume of solution D which gave the maximum
change. (1mk)

(c) Determine the volume of G that reacted with the volume of solution D in
(b) above. (1mk)
(d) Calculate the:-
(i) reacting ratio between sodium hydroxide and acid D.
(Assume that the volume ratio is the same as the mole ratio). (1mk)
(ii) the number of moles of sodium hydroxide, solution G used. (1mk)
(iii) the molar heat of neutralization between sodium hydroxide and the acid.
(Density of the solution = 1gcmˉ³) sp. ht. capacity = 4.2kJkgˉ¹kˉ¹) (2mks)

(a) You are provided with solution Q.
(i) To about 1cm³ of Q add drops of 2.0M sodium hydroxides.

(ii) Dip a metallic spatula in solution Q and burn it directly on a non-luminous flame.

(iii) To about 1cm³ of Q add three drops of 1.0M barium nitrate solution provided and keep the mixture.

(iv) To the mixture in (iii) above add a few drops of 2.0M hydrochloric acid drop wise till in excess.

(v) To about 1cm³ of Q add three drops of acidified potassium dichromate (VI) solution.

(b) (i) To about 2cm³ of solution B1 in a test tube add 2-3 drops of bromine water.

(ii) To about 2cm³ of solution B1 in a test tube add 2-3 drops of acidified of potassium manganate (VII) solution.

(iii) To the remaining solution B1 test with both blue and red litmus.