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(a)(i) It is the splitting of a heavy nucleus into smaller nuclei accompanied by the release of large amount of energy. (ii)\(^{238}_{92}U\) and ends with\(^{230}_{90}Th\) + \(2^{4}_{2}He\) + \(2^{o}_{-1e}Th\) \(\alpha\) [articles = 2 \(\beta\) particles = 2 (b)(i) Equilibrium positicn shifts to the right and more of AB\(_3\) is formed or decrease in concentration of A\(_2\) (ii) Equilibrium shifts to the left and more of A\(_2\) and; B\(_2\) formed / decrease in concentration of AB\(_3\) (iii) No effect. Catalyst affects both forward and backward reactions equally. (c) For a constant cation Na\(^+\) lattice energy decreases with ircreases in size of the anion / decrease in electronegativity of the anion. F\(^-\), Br\(^-\), I\(^-\) increasing order of size. Hence the decreasing crder ofilattice energy. (d)(i) NO\(_2\) is an oxidizing agent (ii) NO\(_2\) is acting as an oxidizing as well as reducing agents OR acid anhydride. (e)(i) Fe\(_2\) O\(_3\) + 3CO --> 2Fe + 3CO\(_2\) (ii) CaCO\(_3\) —› CaO + CO\(_2\), CaO + SiO\(_2\) \(\to\) CaSiO3 (iii) C + O\(_2\) —> CO\(_2\), CO\(_2\) + C \(\to\) 2CO (f) Coke I Coal Tar / Coal Gas /Ammonical Liquor (ii) Coke — Solid fuels I production of water gas, extraction of ME Coal Tar — Synthesis of chemicals — perfumes, dyes, paints, drugs, plastic and explosives, etc. Coal Gas — as fuels in homes and industries Ammonical liquor — production of (NH\(_4\))\(_2\) SO\(_4\) for fertilizer

(a)(i) Structural isomers are compounds with the same molecular formula but different arrangement of constituent at / or different structures (ii) CH\(_3\) CH\(_2\) CH\(_2\) CH\(_2\) OH (b)(i) C\(_5\)H\(_{12}\) + C\(_2\) \(to\) C\(_5\) H\(_{11}\)CI + HCI (ii) (iii) Light act as catalyst (iv) Pentane C\(_2\)H\(_{12}\) would come out first Pentane has a lower molar mass (72) as compared to chloropentane (C\(_5\)H\(_{12}\)CI) (86.5) Hence weaker inter- molecular forces — van der waals' forces (V) C\(_4\)\(H_8\)CI\(_{12}\) (c)(i) (ii) (d)(i) (ii) %N = \(\frac{0.0313}{ 0.309}\) x 100 = 10.1% %0 = 100 — (60.5 + 6.5 + 10.1) = 22.9 C; \(\frac{60.5}{12}\) H; \(\frac{6.5}{1}\) N; \(\frac{10.1}{14}\) O; \(\frac{22.9}{16}\) C; \(\frac{5.04}{0.72}\) H; \(\frac{6.5}{0.72}\) N; \(\frac{0.72}{0.72}\) O; \(\frac{1.43}{0.72}\) Empirical formula — C\(_7\)H\(_9\)NO\(_2\)

a)(i) It is a measure of the tendency of an element to form ions in solution relative to the tendency of hydrogen atoms to form ions in solution at standard conditions (at 298K and 1 atom and 1 molar concentration) (ii) Concentration, Temperature, Pressure. — To predict the direction/feasibility of a chemical reaction — To calculate the e.m.f of a cell — To predict the standard potential of unknown elements. (v) = Emf = E^\circ(Right) — E^\circ(Left) = + 0.34 — (— 0.76) V = +1.10V (b)(i) I Oxidation — a process of electron loss II. Oxidizing agent—an electron acceptor (ii) Separate into half reactions (c) (i) Neutral (ii) Acidic (iii) Amphoteric (iv) Basic (d) Hydrogen bonding is an intermolecular force between molecules in which hydrogen is attached to a very electronegative atom which has a small size, e.g. N, O, F.

(a)(i) I Biotechnology is the use of biological processes / living organisms to make products for human use. II. Biogas is a fuel obtained from organic waste through the process of anaerobic decomposition (ii) Production of drugs (medical), fertilizer, waste management, production of kenkey, fufu, gars, burukutu / any food or beverage produced from fermentation (domestic), industrial application, etc (b)(i) — Add yeast to cane sugar and leave to stand (at room temperature) — Enzyme sucrose hydrolyse / converts — Enzyme zymase ferments / converts glucose to ethanol and CO\(_2\) — Mixture is distilled to obtain ethanol. ii) Carbon IV oxide (iii) — In aerated drinks — as fire extinguisher — coolant / refrigerant — solvay process — synthesis of Na\(_2\)CO\(_3\) iv) Ethanol from cane sugar is renewable because It is from plants which can be cultivated continuously Ethanol from petroleum is non-renewable because it is from a sou;-c,o, which can get exhausted. Heavy chemicals are chemicals used extensively in industries and are produced in very large quantities. Fine chemicals are chemicals produced in small quantities for specific purposes and to a very higil degree of purity. Heavy chemicals — H\(_2\)SO\(_4\), NaOH, NH\(_3\), CaCO\(_3\), HNO\(_3\), HCI, NaCO\(_3\) bleaching powder, metals (iron, tin, aluminium, Copper, Zinc). Fine chemicals — laboratory / analytical reagents, drugs, dyes, perfumes, photographic reagents, additives, cosmetics. d) O\(_2\), C\(_{12}\)HCI increasing order to deviation The extent of deviation depends on intermolecular forces. HCI is a polar and will have a greater intermolecular attraction than Oxygen and Chlorine. The molar mass of chlorine is greater than that of oxygen hence stronger van der waals forces than oxygen

(a)(i)The atom has small / tiny positively charged centre / nucleus with electrons surrounding the space around the centre nucleus. (ii) Atomic number of an element is the number of protons / electrons in an atom of the element while mass number is the sum of the protons and neutrons in the atom of the element. (iii) Chlorine atom is made up of a mixtire of isotopes and the relative atomic 'mass of chlorine is the average of the isotopic masses. (b)(i) Is the minimum energy required to remove one mole of an electron from c mole of gaseous atom to form one mete gaseous ion. Nucleus with — High melting / boiling point Protons Ability to conduct electricity in the molten state or in solution — Solid at room temperature — Soluble in water or polar solvents / insoluble in non-polar solvents. (iii) — Atoms of the elements in each pair have the same number of electrons (c)(i) It is a family of organic compounds their outermost shell therefore similar chemical properties. where successive members ditter by — CH\(_2\) molar mass of 14 — with similar chemical properties — which conform to the same general formula — which show gradation of physical properties whict, have the same general method of preparation, e.g, alkanes, alkenes, alkanols. (ii) It is a process in which a covalent bond is broken in such a way that the electron pair is completely transfered to one of the atoms resulting in the formation of ions e.g. H — CI —> H\(^+\) + Cl\(^-\) / HCI --> H\(^+\) + Cl\(^-\) (d)(i) — Methyl orange / methyl red / phenolphthalein (ii) — Methyl orange orange / methyl red (iii) — Phenolphthalein. (e) E — NH\(_4\)Cl F — NaOH, KOH or Ca(OH)\(_2\), LiOH, CsOH, Ba(OH)\(_2\), Mg(OH)\(_2\) G — NH\(_3\)

(a)(i) Lime water turns milky with CO\(_2\) because insoluble CaCO\(_3\) / CacO\(_{3(s)}\) is formed. Milkiness disappears when excess CO\(_2\) reacts with CaCO\(_3\) in water medium forming the soluble Ca(HCO\(_3\)\(_2\))/Ca(HCO\(_3\))\(_2\) ii) Calcium hydroxide is not amphoteric. Does not react with an alkali NaOH whereas lead (II) hydroxide is amphoteric, so reacts with excess NaOH (b)(i) Primary standard solution is one whose concentration is known and can be used to standardize another solution OR Primary standard solution is a solution of known concentration prepared from pure / non - deliquescent / non hygroscopic substances. (ii) Molar mass Na\(_2\)CO\(_3\) = 106gmol\(^{-1}\) Molar mass Na\(_2\)CO\(_3\) = C x M x V = 0.15 x 106 x 0.25 = 0.15 x 106 x 0.25 = 3.98g

TEST OBSERVATION INFERENCE (a)(i) C + NaOH\(_{(aq)}\) + warm (ii) C + HCl\(_{(aq)}\) + BaCl\(_{2(aq)}\) (b)(i) D + NH\(_{3(aq)}\) (ii) D + AgNO\(_{3(aq)}\) + HNO\(^{3(aq)}\) No visible reaction/no pot A colourless gas with pungent/choking/irritating smell evolved. Gas turned damp red litmus blue/formed white fumes with conc HCl vapour No visible reaction while ppt formed Reddish - brown/brown ppt ppt insoluble White ppt ppt insoluble Gas is NH\(_3\) from NH\(_4^+\) SO\(_4^{2-}\) present Fe\(^{3+}\) present Cl\(^-\) or CO\(_3^{2-}\) Cl\(^-\) present

ROUGH (cm\(^3\)) 1st Titration (cm\(^3\)) 2nd Titration (cm\(^3\) Initial Burette Reading 27.00 49.50 36.00 Initial Burette Reading 01.00 26.00 12.40 Vol. of Acid Used(cm\(^3\)) 26.00 23.50 23.60 Average Titre = \(\frac{23.50 + 23.60}{2}\) = 23.55cm\(^{3}\) (b)(i) Concentration of B in moldm\(^{-3}\) Molar mass of NaOH = 23 + 16 + 1 = 40g mol\(^{-1}) concentration of B = \(\frac{3.90}{40}\) = 0.0975 mol dm\(^{-1}\) (ii) concentration of BAin mol dm\(^{-3}\) \(\frac{C_AV_A}{C_BV_B}\) = \(\frac{1}{2}\) C\(_A = \frac{C_BV_B}{2V_A}\) C\(_A\) = \(\frac{0.975 \times 25}{2 \times 23.55}\) = 0.0518 mol dm\(^{-3}\) (ii) Molar mass of H\(_2\)Y Molar mas of H\(_2\)Y = \(\frac{6.22}{0.0518}\) = 120 gmol\(^{-1}\) (c)(i) Less than 7 (ii) Greater than 7 [C = (NH\(_4\))\(_2\)SO\(_{4(aq)}\); D = FeCl\(_{3(aq)}\)

Hostile; showing or feeling opposition or dislike; unfriendly. Amicable; having or displaying a friendly and pleasant manner.

construct; build or make (something, typically a building, road, or machine). Demolish; pull or knock down (a building).

For something to be distressed, it is suffering from extreme anxiety, sorrow, pain or setback. A buoyant economy is a successful one in which there is a lot of trade and economic activity.

Real; actually existing as a thing or occurring in fact; not imagined or supposed. Imaginary; existing only in the imagination.

Efficiency; able to accomplish something with the least waste of time and effort Incompetence; inability to do something successfully; ineptitude.

flourishing; developing rapidly and successfully; thriving. Declining;becoming smaller, fewer, or less; decreasing.

Cultured; characterized by refined taste and manners and good education. Barbaric; primitive; unsophisticated.