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3901

Calcium chloride is an ionic compound. Which of the following statements account for its ionic character?

I. Calcium has high ionization energy.  II. Calcium has low ionization energy. III. Chlorine has high electron affinity. IV. Chlorine has high Ionization energy.

  • A. I and Il only
  • B. I, II and IV only
  • C. II, IIl and IV only
  • D. I, II, III and IV
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3902

An example of a biodegradable pollutant is?

  • A. plastic
  • B. sewage
  • C. carbon (II) oxide
  • D. hydrogen sulphide
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3903

(a)(i) State Faraday's first law of electrolysis. (ii) Distinguish between a strong electrolyte and a weak electrolyte

(b) State one chemical property of ethyne.

(c)( i) What is meant by the tern unsaturated hydrocarbon? (ii) Complete the following reaction equation: CH\(_3\) + CH\(_3\)OH-> (iii) Name the major product formed in the cation stated in 1(c)(ii).

(d) State one way by which the rate of esterification could be increased.

(e) Consider the reaction represented by the following equation: Zn + H\(_2\)SO4 → ZnOS\(_4\) + H\(_2\) . If 3.75g of Zn dust was added to excess H\(_2\)SO\(_4\). Calculate the number of molecules of hydrogen gas produced. [ Zn = 65.0, Na = 6.02 X10\(^23\) ].

 (f) State one effect of global warming.

(g) Consider the following reaction equation:

A. Pb(NO\(_3\)) +H\(_2\)S --> PbS + 2HNO\(_3\);

B. H\(_2\) + C\(_2\)H\(_4\) → C\(_2\)H\(_6\).

C. Zn(OH)\(_2\) + 2OH → [ Zn(OH)\(_4\) ]\(^2\).

(i)  Which of the equations represent(s) redox process? (ii) State the change in Oxidation number of the species that are oxidized or reduced. (h)(i) State two of the main concepts of Bohr's model of the atom. (ii) State the limitations of Bohr's model. (i) List three factors that could influence the equilibrium position of a reversible reaction. (j) Calcium trioxocarbonate(iv) powder is added to separate equimolar solutions of hydrochloric acid and ethanoic acid. State one: (i) similarity in the observation in both reactions: (ii) difference in the observation in both reactions.

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3904

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(a) Consider the following compounds:  (i) What is the relationship between the compounds labeled A and B? (ii) Name each of compounds A and B. (iii) Will the chemical properties of compounds A and B be the same? (iv) Give the reason for the answer stated in 2(a)(ii).

(b)(i) Give two characteristic features of boiling, (ii) What would be the effect of each of the following conditions on the boiling point of water? I. Addition of crystals of sodium chloride. II. Reduction of the atmospheric pressure. (iii) State one way in which boiling differs from evaporation.

(c)(i) Differentiate between an unsaturated solution and a saturated Solution. (ii) State two ways by which a saturated solution could be made to dissolve more solute. (iii) State one factor that could affect the solubility of a solid in a liquid. (d)(i) Define the term mole .

(ii) Consider the following reaction equation: MgO + 2HCI → MgCl\(_2\) + H\(_2\). What mass of magnesium Oxide is needed to neutralize 25.0 cm3 of 0.1 mol dm-3 hydrochloric acid? [O= 16.0; Mg = 24.0]. (e) State three physical properties of metals.

 

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3905

(a) In the laboratory preparation of dry chlorine gas, state the: I. reagents used; II. drying agent III. the mode of collection.

(i) Write the equation for the preparation of chlorine gas. (iii) Write an equation to show how chlorine reacts with hot concentrated NaOH.

(b)i). Name the main raw materials used for the extraction of iron in the blast furnace. (ii) Write the equations of the reactions taking place in the blast furnace.

(iii) What is the name given to the iron obtained directly from the blast furnace? (iv) State why the iron named in 4(b)(iii) have a relatively low melting point?

(c) The following equation represents one of the reaction steps involved in the contact process: 2SO\(_2\) + O\(_2\)   2SO\(_3\) ΔH = -395.7 kJ mo-l

(i) Why is the SO\(_3\) produced during the reaction not dissolved directly in water to form H\(_2\)SO\(_4\)? (ii) Why is the H\(_2\)SO\(_4\) regarded as a heavy chemical? (iii) State the property exhibited by tetraoxosulphate (VI) acid in each of the following reaction equations.

I. Pb(NO\(_3\))\(_2\) + H\(_2\)SO\(_4\)→ PbSO\(_4\) + 2HNO\(_3\) (d) Write a balanced chemical equation for the reaction between propanol and sodium

 

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