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(a)(i) - sodalime does not attack glass apparatus, unlike caustic soda - sodalime is not, deliquescent unlike caustic soda. (ii) - it is a gas at room temperature. - colourless gas. - odourless gas. - slightly soluble in water. -less dense than air. (iii) I. % Carbon Hydrogen 82.76 17.24 82.76 17.24 12 1.00 6.90 17.24 6.90 6.90 1 2.5 2 5 II. Emperical formula = C\(_2\)H\(_5\) Molecular formula = C\(_2\)H\(_5\)n = VD x 2 [(12 x 2) + (1 x 5)]n = 58 29n = 58 n = 2 molecular formula = (C\(_2\)H\(_5\))\(_2\) = C\(_4\)H\(_{10}\) (b) (i) Tha existence of two or more compounds with the same molecular formula but different molecular structures/different arrangement of atoms. (iii) ethanol methoxymethane (iv) The two isomers belong to different homologous series/they have different functional groups. (c) - functional groups - number of atoms of different elements - types of elements - types of bonds - percentage composition of the elements in a compound - spatial arrangements of atoms in a molecule (d) Pass each of the gases into (acidified) KMO\(_4\)/ bromine water/bromine inCCl\(_4\)/ bromine propene decolourizes bromine water/KMnO\(_4\)/bromine in CCI\(_4\)/bromine whereas propane does not.

(a)(i) Water is a universal solvent because it can dissolve many substances. water is polar and as a result, it can dissolve ionic solutes as well as partially ionic/polar covalent substances (ii) Add water to anhydrous copper (II) tetraoxosulphate (VI) salt, colour changes from white to blue. OR Add water to anhydrous cobalt (II) ch!oric!e, colour changes from blue to pink. (b)(i) I. OH\(^-{_(aq)}\) \(\to\) 2H\(_2\)O\(^-{_(l)}\) + O\(_{2(g)}\) + 4e\(^-\) II. 2H\(^+_{(aq)}\) + 2e\(^-\) --> H\(_{2(g)}\) OR 4H\(^+_{(aq)}\) + 4e\(^-\) --> 2H\(_{2(g)}\) Ill. 2H\(_2\)O\(_{(l)}\) -> OH\(_{2(g)}\) + O\(_{2(g)}\) OR 4OH\(^-_{(aq)}\) + 4H\(^+_{(g)}\) --> 2H\(_2\)O\(_{(l)}\) + 2H\(_{2(g)}\) + O\(_{2(g)}\) (ii) Quantity of electricity = 1 x t = 1.25 x 40 x 60 = 3000C For 1 mole of O\(_2\) formed at the anode, 4e\(^-\) are generated Volume of O\(_2\) formed by 3000C = \(\frac{3000}{96500}\) x \(\frac{1}{4}\) mole O\(_2\) = 7.77 x 10\(^{-3}\) moles 1 mole O\(_2\) occupies 22.4 dm\(^{3}\) at s.t.p. mole of O\(_2\) = 7.77 x 10\(^{-3}\) x 22.4 dm\(^{3}\) = 0.174dm\(^{3}\)/174 cm\(^{3}\) OR From the equation at anode; 4 x 96500C = 22.4 dm\(^{3}\) 3000C = \(\frac{22.4 \times 3000}{4 \times 96500}\) = 0.174dm\(^{3}\) / 174 cm\(^{3}\) (c)(i) 2Au\(_{(s)}\) + 3Cl\(_{2(g)}\) \(\to\) 2AuCI\(_{3(s)}\) (ii) Amount of Au= \(\frac{1.2}{197}\) = 0.00634 mole Amount of Cl\(_2\) = \(\frac{1.744}{71}\) = 0.0246 mole. From equation: 2 moles of Au = 3 moles of Cl\(_{(2)}\) .-. 0.00634 mole of Au = \(\frac{0.00634 \times 3}{2}\) = 0.00951 mole Amount of CI\(_2\) available = 0.0246 mole but amount required by all the Au for the reaction = 0.00951 CI\(_2\) is in excess. (iii) Excess amount of CI\(_2\) = amount available - amount used = 0.0246 - 0.00951 = 0.015 mole.

(a)(i) coke (ii) ammoniacal liquor/coal tar (iii) coal gas (b) (i) methane (ii) because sulphur is removed in the gasification process/it does not contain sulphur or sulphur compounds. (c)(i) C\(_{(S)}\) + O\(_{2(g)}\) --> CO\(_{2(g)}\) (ii) I. is a gas at room temperature - it is a colourless gas - it is an odourless gas - it is denser than air - it readily liquefies and solidifies/easily compressible. II. - reacts with alkali to form trioxocarbonate (IV) - it is soluble in water - reacts with (burning) Mg to form MgO - reacts with red hot carbon to form CO - It is weakly acidic in water - it does not support combustion. (d)(i) I. diamond graphite II. -coal/ lampblack/soot/carbon black - coke - charcoal. (ii) I. Diamond - as a cutting tool - as jewellery; Graphite - as a lubricant - as an electrode - as pigment in paints - as neutron moderators in nuclear reactors. II. Coke - as a fuel -as a reducing agent/in the extraction of metals - preparation of carbides - for making water gas/producer gas. Coal - as a fuel -as a starting material for chemicals. Charcoal - as a fuel - as absorbent/in gas mask - in the purification of gases - in the recovery of industrial solvent - for removing colouring matter from substances Lampblack/Soot/carbon black: - to colour rubber tyres - to make boot/shoe polish - to make printers ink - to make black paint - typewriting ribbons - carbon paper. (e)(i) I. S\(_{(s)}\) + O\(_{2(g)}\) --> SO\(_{2(g)}\) II. 2SO\(_{2(g)}\) + O\(_{2(g)}\) \(\rightleftharpoons\) 2SO\(_{3(g)}\) III. SO\(_{3(g)}\) + H\(_2\)SO\(_{4(g)}\) -> H\(_2\)S\(_2\)O7\(_{7(l)}\) IV. H\(_2\)SO7\(_{7(l)}\) + H\(_2\)O\(_{(l)}\) -> 2H\(_2\)SO\(_{4(l)}\) (ii) I. - dehydrating agent II. precipitating agent/displacement agent.

Handsome; substantial, large in size meagre; scanty, inadequate, small

Novice; a person new to and inexperienced in a job or situation. veteran; a person who has had long experience in a particular field.

fame; the state of being known or talked about by many people, especially on account of notable achievements. obscurity; the state of being unknown, inconspicuous, or unimportant.

Insignificant; too small or unimportant to be worth consideration. Crucial; of great importance.

firm; strongly felt and unlikely to change. flexible; ready and able to change so as to adapt to different circumstances.

Loyal; giving or showing firm and constant support or allegiance to a person or institution. unfaithful; not adhering to vows, allegiance, or duty

Convict; declare (someone) to be guilty of a criminal offence by the verdict of a jury or the decision of a judge in a court of law. Acquitted; free (someone) from a criminal charge by a verdict of not guilty.

Reconciling; restore friendly relations between. separating; cause to move or be apart.

Deteriorated; become progressively worse.

One very important aspect of human relationship is mutual trust. mutual; (of a feeling or action) experienced or done by each of two or more parties towards the other or others.

The two tasks were performed simultaneously and we were able to finish early. simultaneously; at the same time.

The committee is charged with finding a lasting solution to the crisis