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Ethene is an alkene, meaning it has a carbon to carbon double bond. When Bromine is added, an addition reaction occurs forming 1,2 dibromoethane. C2H4 + Br2 -> C2H4Br2

Fresh palm wine contains natural sugars (like glucose) that initially ferment via yeast into ethanol (alcohol). When the palm wine is left exposed to air for a few days, airborne aerobic bacteria—such as Acetobacter—utilize the oxygen to oxidize the ethanol into ethanoic acid (also known as acetic acid) and water. Ethanoic acid is the main component of vinegar, and its accumulation gives the wine its characteristically sharp, sour taste.

To distinguish between ethene and ethyne: i Add a few drops of ammonical copper(I) chloride to each of ethylene (ethene) and acetylene (ethyne). No change will be observed in the case of ethylene (ethene) but in the case of acetylene (ethyne), a red precipitate of copper acetylide is formed. similar result ii) When ammoniacal Silver Nitrate (AgNO3) is added to Ethyne then it gives white precipitates. But when Ammoniacal silver nitrate is added to Ethene then no reaction occurs and no precipitates obtain.

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.

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

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

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

Chlorine(Cl) has configuration 2,8,7 but Chlorine ion (Cl-) has 18 electrons and configuration 2,8,8. Here is the reason: Chlorine has 17 electrons, and these are distributed in shells (or energy levels) as follows: 2 in the first shell, 8 in the second, and 7 in the third.This is represented as 2,8 7. Chlorine can gain one electron to achieve a stable electron configuration, resembling that of the noble gas Argon. When chlorine gains an electron, its electron configuration becomes 2, 8, 8, making it a chloride ion (Cl⁻). The 2,8,8 configuration means the outermost shell is full with 8 electrons, which is the octet rule, making the ion stable.

(a)(i) Volume (V) decreases as pressure (P) increases or V a PV = K where K is a constant of proportionality (ii) Boyles law (iii) P\(_1\)V\(_1\) = P\(_2\)V\(_2\) \(\frac{P_1V_1}{V_2}\) = \(\frac{1 \times 4}{3.2}\) \(\frac{2 \times 42}{3.2}\) = \(\frac{4 \times 1}{3.2}\) = 12.5 atm (b)(i) Salt bridge is to maintain electrical neutrality in each cell / to allow cations and anions move from o electrode compartment to the other. (ii) Negative ions Because the cathode is positively charged. (iii) (I) 2 Ag\(^+_{(aq)}\) + Zn\(_{(s)}\) \(\to\) 2Ag\(_{(s)}\) + ZnAg\(^+_{(aq)}\) E^\circ = E^\circ cathode — E^\circ Anode = + 0.80 – (-0.76V) = +1.56V (II) Ag\(^+\) + e\(^-\) \(\to\) Ag 108g of Ag = 1 mole of e\(^-\) Thus 3.3g of Ag = \(\frac{1}{108}\) = 0.03mol (III) 1 mole e\(^-\) = 96500C 0.03 mole e\(^-\) = 96500 x 0.03 = 2.39 x 10\(^3\)C. c)(i) (I) Activation energy is the minimum amount of energy required to effect a chemical reactioniminim amount of energy required by reactants to form products. (II) Exothermic reaction is a reaction in wh energy is released to the surrounding. (ii) Ammonium chloride dissolved in water. –Thermal decomposit of CaCO\(_3\) (iii) Activated complex must be attained / formed for reactants to form products.

(a)(i) V and Y (ii) X (iii) Z (iv) W (v) V and Y (vi) V and Y (b)(i) — 2 or 2— (ii) Akali metals (c)(i) V\(_2\) W (ii) Bond — ionic / electrovalent V can readily lose its electron W can readily accept electrons to attain stability. (d)(i) A ccmpond formed by two atoms which donate equal no of electrons that are shared between them such that each achieves a stable octet. (ii) * electronegativity (difference) * ionization energy * electron affinity (iii) MgO — ionic / eiectroyalent NH\(_3\) — covalent Fe — metallic (iv) Intermolecular forms. are attractive forces that operate between molecules and influence the properties of the substance.

(a) Solubility is the maximum amount of solute that would dissolve / be contained in 1 dm\(^3\) of solution at a given temperature. (b)(i) (ii) At 35^\circ solubility = 0.50 to 0.55 moldm\(^{-3}\) range (iii) Solubility @ 55^\circC = 0.95 to 0.98 moldm\(^{-3}\) 1 moldm\(^{-3}\) of salt Z = 0.97; 100 = 97g 100cm\(^{-3}\) will contain = \(\frac{97 \times 100}{100}\) = 9.7g Solubility @ 35^\circC = 0.54moldm\(^{-3}\) 1 drn\(^{-3}\) contain = 0.54 x 100 = 54g 100cm\(^{-3}\) will contain 54 x100 = 5.4g 10 Mass of salt that would crystallize out = 9.7 - 5.4 = 4.3g (c)(i) (I) Al\(_2\)O\(_{3(s)}\) + 6HCl\(_{(aq)}\) \(\to\) 2AlCl\(_{3(s)}\) + 3H\(_2\)O\(_{(l)}\) (II) Al\(_2\)O\(_{3(g)}\) 2NaOH\(_{(aq)}\) + 3H\(_2\)O\(_{(l)}\) \(\to\) 2NaAl(OH)\(_4\) (ii) Amphoteric (iii) ZnO / PbO / SnO /Al\(_2\)O\(_3\) d)(i) I [Al(H\(_2\)O)\(_6\)]\(^{3+}\) = x + (0) = +3 x = +3 Al = +3 (II) NaH = 1+ x = 0 x = —1 H = — 1 (ii)(I) Copper (II) tetraoxosulphate VI pentahydrate (II) Calcium tripxocarbonate IV (III) Potassium tetraoxomanganate VII.

(a)(i) It is an atom or group of bonded atoms that is responsible for the chemical behaviour of an organ compound (ii)(I) — OH or hydroxyl group or alkanol (C) C\(_4\) H\(_8\) + H\(_2\)SO\(_4\) \(\to\) C\(_4\)H\(_8\)HSO\(_4\) C\(_4\)H\(_9\)HSO\(_4\) + H\(_2\)O \(\to\) C\(_4\)H\(_8\)OH + H\(_2\)SO\(_4\) OR CH\(_2\) = CHCH\(_2\)CH + H\(_2\)O \(\to\) CH\(_3\)OHCHCH\(_2\)CH\(_3\) OR C\(_4\)H\(_8\) + H\(_2\)O \(\to\) C\(_4\)H\(_8\)OH (d)(i) (I) Conc. H\(_2\)SO\(_4\) / H\(_3\)PO\(_4\) (II) Acidified KMnO\(_4\) / K\(_2\)Cr\(_2\)O\(_7\) / Na\(_2\)Cr\(_2\)O\(_7\) (Ill) Ethanol and Conc. H\(_2\)SO\(_4\) (e)(i) (I) Effervescence occurs (II) Yellow precipitate (III) Bromine water decolourized (ii) (I) or — COOH or alkanoic group (II) CH\(_3\)CHOH / CH\(_3\) adjacent to CHOH (III) C = C or carbon — carbon double bond

(a) X — CaCO\(_3\) Y — Ca(NO\(_3\))\(_2\) (b)i) 2NH\(_{3(g)}\) + 3CuO\(_{(s)}\) \(\to\) 3Cu\(_{(s)}\) + 3H\(_2\)O\(_{(g)}\) + N\(_{2(g)}\) (ii) *Explosion may occur. *Because ammonium dioxonitrate (Ill) is unstable and decomposes exothermically. (iii) *Manufacture of NH\(_3\) etc *liquid nitrogen as cooling agent * gas carrier in gas chromatography * as preventive against oxidation. (c)(i) Dilute H\(_2\)SO\(_4\) reacts with CaCO\(_{3(s)}\) to form our insoluble salt CaSO\(_4\), which covers the CaCO\(_3\), thus preventing further reaction or production of CO\(_{2(g)}\) , after a short time. (ii) Conc. H\(_2\)SO\(_4\) reacts with ammonia to form a salt (NHq)\(_2\)SO\(_4\) (d)i) Physical Properties of Metals * / ductility *Good conductor of heat / electricity *Sonorous *relatively high density * high melting / boiling points (ii) Chemical Properties of Metals * Ionize by electron loss / reducing agent *Form basic oxides *(some) displace hydrogen from dilute oxide *A more reactive metal displaces or loss reactive metal from a solution cf its salt. (e)(i) (I) Oxidation no of CI = 0 (II) Oxidation no of CI = + 5 (ii) Oxidation no of V = + 5 (f)(i) Half - life is the time taken for half of the total number of atoms in a given sample of the element to decay. (ii)(I) Q is more stable (II) Stability is dependent on half life, the longer it takes substance to decay the more stable it is.

(a)(i) (ii) Rate = change in concentration = \(\frac{0.002 — 0.000}{80}\) = \(\frac{0.002}{80}\) = 2.5 x 10\(^{-5}\) moldm\(^{-3}\) sec\(^{-1}\) (b) (i) (I) Manufactise of baking powder (II) Manufacture of tetraoxosulphate (VI) plaster of paris (P.O.P.) (III) Cement making, extraction of iron, solvay process, manufacture of glass, manufacture of putty (ii) (I) Conc. H\(_2\)SO\(_4\) (II) Conc. H\(_2\)SO\(_4\) (III) CaO / Silica gel. (c)(i) C\(_{(s)}\) + O\(_{2(g)}\) \(\to\) CO\(_{2(g)}\) (II) 12g C gives 1 mol CO\(_2\) 2. 5g C gives \(\frac{1 \times 2.5}{12}\) = 0.208 mol. (iii)(I) Extraction of metals, manufacturer of fuel, as gaseous fuel. (II) * Manufacture of fizzy drinks * Fire extinguisher * Cooling nuclear reactors *Refrigeration. (d) Mole: Fe = \(\frac{28.1}{56}\); Cl = \(\frac{35.7}{35.5}\); H\(_2\)O = \(\frac{36.2}{18}\) Mole ratio; Fe = \(\frac{0.5}{0.5}\); Cl = \(\frac{1}{0.5}\); H\(_2\)O = \(\frac{2}{0.5}\) Fe =1; Cl = 2; H\(_2\)O = 4 (e)(i) Mercury (H\(_g\)) (ii) Bromine (Br\(_2\))