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3411

(a)(i) Describe briefly the industrial preparation of ammonia.

(ii) Write a balanced equation for the reaction in (a)(i).

(iii) State one way of increasing the yield of ammonia in 4(a)(i).

(iv) State two uses of ammonia.

 

(b) Describe briefly, one chemical test for each of the following gases in the laboratory: (i) hydrogen; (ii) carbon (IV) oxide; (iii) oxygen.

 

(c)(i) State the composition of water gas.

(ii) List two uses of water gas.

 

(d) Describe briefly a simple experiment to determine the type of hardness in a sample of water.

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3412

(a)(i) Describe briefly how trioxonitrate (V) ions could be tested for in the laboratory.

(ii) State two uses of each of the following compounds: I. sodium chloride; II. sodium trioxocarbonate (IV).

 

(b) Write balanced equations for the reactions involved in the extraction of iron in the blast furnace.

(ii) State Faraday's first law of electrolysis.

(iii) State two applications of electrolysis.

 

(c) Concentrated tetraoxosulphate (VI) acid is added to sugar crystals in a beaker. State what would be observed. Explain briefly your answer.

 

(d) Write an equation for the reaction of zinc powder with:

(i) dilute tetraoxosulphate (VI) acid;

(ii) concentrated tetraoxosulphate (VI) acid.

 

(e) What property of concentrated tetraoxosulphate (VI) acid is shown in (d)(ii)

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3413

(a) What are nucleons?

(b) State Graham's law of diffusion.

(c) Explain briefly why aluminium does not corrode easily.

(d) State three examples of periodic properties.

(e) State two reasons why real gases deviate from ideal gas behaviour.

(f) List three uses of fractional distillation in industry.

(g) What factors determine the selective discharge of ions at the electrodes during electrolysis?

(h) State the type of reaction represented by each of the following equations:

(i) C\(_2\)H\(_6\) + Br\(_2\) ---> C\(_2\)H\(_5\)Br + HBr;

(ii) C\(_2\)H\(_4\) + .Br\(_2\) ---> CH\(_4\)Br\(_2\)

 

(i) Name the products formed when butane burns in limited supply of air.

(j) List three methods of separating a solid from a liquid.

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3414

(a) Consider the following atoms: \(^R_T\)X; \(^S_T\)X.

(i) State the phenomenon exhibited by the two atoms.

(ii) What is the difference between the atoms?

(iii) Give two examples of elements that exhibit the phenomenon stated in (ai)

(iv) lf T is 17, write the electron configuration of the element

 

(b)(i) State two differences between metals and-non-metals with respect to their:

I. physical properties;

2. chemical properties.

(ii) Give one example of each for the following compounds:

I. an amphoteric oxide;

II. a hydride which evolves hydrogen when reacted with water;

Ill. a trioxocarbonate (IV) salt which is readily decomposed on heating;

IV. a chloride salt which is readily hydrolyzed in water.

 

(c)(i) State three characteristic properties of transition metals. 

(ii) Write the electron configuration of \(_{30}Zn\)

(iii.) Explain briefly why zinc is not considered as a typical transition element.

 

(d) Consider the reaction represented by the following equation:- Na\(_2\)CO\(_{3(aq)}\) + MgCl\(_{2(aq)}\) ----> 2NaCl\(_{(aq)}\) + MgCO\(_{3(aq)}\). Calculate the mass of sodium trioxocarbonate (IV) needed to produce 3.36 of magnesium trioxocarbonate (IV). [C = 12.0, O = 16.0, Na = 23.0, Mg = 24:0 ]

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3415

(a) (i) Draw the structures of the isomers of the alkene with molecular formurat C\(_4\)H\(_8\)

(ii) State the class of alkanols to which each of the following compounds belongs:

I. CH\(_3\)C(CH\(_3\))\(_2\)OH;

II. CH\(_3\)CH(CH\(_3\))CH\(_2\)OH;

III. CH\(_3\)CH\(_2\)CH(CH\(_3\))OH.


(b) (i) Write the formulae of the products formed in the following reactions:
I. CH\(_3\)CH\(_2\)COOH \(\frac{K_{(s)}}{}\)

II. CH\(_3\)CH\(_2\)COOH. \(\frac{C_4H_6OH, heat}{Conc.H_2SO_4}\)

III. CH\(_3\)CH\(_2\)CH\(_2\)CH\(_2\)OH \(\frac{H^+/KMnO_4}{(excess)}\)

(ii) Name the major product(s) of each of the reactions in (b)(i).

 

(c) A gaseous hydrocarbon R of mass 7.0 g occupies a volume of 2.24 dm\(^3\) at s. t.p. If the percentage composition by mass of hydrogen is 14.3, determine its:

(i) empirical formula;

(ii) molecular formula. [ H = 1.00, C = 12.0, Molar volume of gas at s.t.p, = 22.4 dm\(^3\) ]

 

(d) Define structural isomerism.

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