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No expanded working has been attached for this question yet. The verified answer is Option E.

No expanded working has been attached for this question yet. The verified answer is Option D.

No expanded working has been attached for this question yet. The verified answer is Option D.

No expanded working has been attached for this question yet. The verified answer is Option B.

(a)(i) For removing colouring matter or for absorbing gases. (ii) Solution of magnesium ash turns red litmus blue. MgO + H\(_2\)O = Mg(OH)\(_2\). Solution of phosphorus fumes turns blue litmus red (b) Add Na\(_2\)CO\(_{3(aq)}\) or NaHCO\(_{3(aq)}\) separately. - CH\(_3\)COOH gives a colourless gas that turns lime water milky i.e. CO\(_3\) - CH\(_3\)CH\(_2\)OH gives no visible reaction. We can also use the acidified KMnO\(_4\) rxn, or iodoform rxn or litmus test to distinguish (c) A stated volume of the solution is pipetted into a clean 250cm\(^3\) volumetric flask. Distilled water is added and the solution is made up to the mark with more distilled water by means of dropping pipette.

24mg = 1 mole of magnesium and 32g of O2 = mole of O2

(a) 1s\(^2\)2s\(^2\)2p\(^6\)3s\(^2\)3p\(^3\) (b) Cu\(^2\) + 4NH\(_3\) —> Cu(NH\(_3)^{2+}_4\) (Deep blue in colour)

(a) The non-flamable nature and the high density of carbon (IV) oxkfe makes it suitable for extinguishing fires. (b) The cation exchange resin is a complex substance which has its cation part capable of being replaced by the calcium ion (Ca\(^{2+}\)) from the hard water run over the resin. The water running out of the resin column is the softened water

(a) The test carried out shows the hydrocarbon x is an alkene. The smallest number of the family is ethene (C\(_2H_4\)) If (\(C+2H_4)_x = 56\) i.e. (28)x = 56 x = \(\frac{56}{28}\) = 2 2(\(C_2H_4\)) = C\(_4\)H\(_8\) (b)

(a) \(^{238}_{94}U \to ^{234}_{92}Th + Y\) From above balanced equation \(^4_2Y = ^4_2He\) (b) Cathode ray experiment Observations Deductions The cathode rays throw a shadow at the anode. The rays will turn a light paddle wheel is the tube. Deductions The rays are negatively charged and hence the attraction to the anode. The rays therefore have momentum and mass.

a) A collision between reactants may not produce new species because the reactants may the activation energy. (b) AlCl\(_{3(g)}\) + H\(_2\)O\(_{(l)}\) \(\to\) Al(OH)\(_{3(aq)}\) + HCl\(_{(aq)}\) of the two products of aluminium chloride HCl is a strong acid which will make the medium acidic.

(a) \(\Delta\)C = \(\Delta\)H - T\(\Delta\)S (free energy) (enthalpy) (Temperature x Entropy) (b)(i) Entropy is positive (ii) Entropy is positive (iii) Entropy is negative.

(a)(i) (ii) Resonance structure (b)(i) Benzene can be used to make important chemicals such as disinfectant and perfumes. (ii) Benzene can be obtained from coal tar, a destructive distillate of coal.

(a) Bromine — Chlorine — Fluorine Increasing order of electronegativity. The above order is as a result of their decreasing order of atomic size from bromine to fluorine. The smaller the atom, the more the atom is capable of attracting electron to itself. (b) Iodine is precipitated as the molecular iodine by chlorine gas because chlorine, the more electronegative halogen than iodine displaces the iodine from its seat of combination in the starch iodine paper.

(a)(i) Diamond is buckled hexagonal giant molecule (ii) Iodine is covalent molecule. (iii) Sodium chloride is face - centred cubic (b)(i) An alloy of tin is bronze (Cu and Sn) (ii) Tindichloride (SnCl\(_2\)).