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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.

(a)(i) Characteristics of homologous series: –All members can be represented by a general molecular formular. –Each member of the series differs from the next by a constant/Fixed number of atom-CH\(_2\)/Successive member differs by CH–All members of the group have similar chemical proterties. –All members have same functional group. –All members of the; roup are prepared using similar/same general methods. All members of the series show a gradual change in physical properties (e.g. density, solubility, etc). (ii) Groups of compounds which form such a series: –Alkanes –Alkenes –Alkynes –Alkanols –Alkanoic acid –Alkanoates. (b) A saturated organic compound A containing two carbon atoms reacted with ethanoic acid in the presence of a mineral acid to form a compound B with a sweet smell: The functional group present in A. Hydroxy/Hydroxyl. (ii) Structure of A. (iii) Chemical equation to show the formation of B: CH\(_3\)COOH + CH\(_3\)CH\(_2\)OH \(\rightleftharpoons\) CH\(_3\)COOH\(_2\)CH\(_3\) + H\(_2\)O. (iv) Name of compound B: Ethyl ethanoate (c)(i) Balance equation for reaction between Ethyne and Excess bromine: C\(_2\)H\(_2\) + 2Br\(_2\) --> C\(_2\)H\(_2\) Br\(_4\) OR H— C \(\equiv\) C— H H 2Br\(_2\) —> H-CBr\(_2\)-CBr\(_2\)-H (ii) IUPAC name of the product of the reaction in (c)(i) 1,1, 2, 2–tetrabromoethane. (iii) Conditions under which cracking takes place: –High pressure –High temperature –Presence of a suitable catalyst. (d)(i) Preparation of ethanol from starch: Treat starch with malt, diatase, convet starch to maltose. 2(C\(_6\) H\(_{(10)}\)O\(_5\) )n + nH\(_2\) O --> nC\(_{(12)}\) H\(_{(22)}\)O\(_{(11)}\). Add yeast. Ezyme maltase convert maltose to glucose. C\(_{(12)}\)H\(_{(22)}\) + H\(_2\)O —> 2C\(_6\)H\(_{(12)}\)O\(_6\). Ezyme zymase convert glucose to maltase to ethanol and CO\(_2\) C\(_6\)H\(_{(12)}\)O\(_6\) —> 2C\(_2\)H\(_5\)OH + 2CO\(_2\). (ii) Properties of starch: –Can be hydrolysed. –Has no taste. –When suspension of starch is warmed, it forms colliodal solution. –It is insoluble in water. –It has no smell. (iii) Reason why starch does not reduce Fehlings solution: It does not contain any free carbonyl group/No alkanol group/No hydrogen attached to the carbonyl group. (iv) Chemical test to confirm the presence of starch: Add a few drops of iodine to a boiled starch. A dark-blue colouration appears.

(a)(i) Gases that could be used to perform the fountain experiment: –Hydrogen chloride. Ammonia (ii) Physical property which makes the gases suitable for the experiment: –The gases are highly/very soluble in water. (b)(i) Definition of Solubility and Saturated Solution: I. Solubility is the maximum amount of soluble in mole or grams that will dissolve in 1 dm\(^3\) of the solvent at that temperature or solubility is the amount of solute that will saturate 1 dm\(^3\) of the solvent at that temperature. II. Saturated solution is a solution that contains as much solute that can dissolve at a particular temperature (in the presence of undissolved solute particles). (ii) Factors that affect the solubility of a solid in a liquid: –Temperature. –Nature of the solute. --Nature of the solvent. (iii) A salt Z of mass 10.2 g was dissolved in 15.4 cm\(^3\)of distilled water at 40^\circC. Calculate the solubility of Z in moldm\(^3\) at 40^\circC. Calculate the solubility of Z in moldm\(^3\) at 40^\circC 1000cm of water = \(\frac{10.2 \times 1000}{15.4}\) = 662.34g Solubility in moldm\(^3\) = \(\frac{662.34}{331}\) = 2.0moldm\(^3\)

(a) Definition of Electrochemical Cell: Electrochemical cell is defined as a device/cell which converts chemical energy to electrical energy/or electricity is generated by a chemical change. (b) Aluminium can be prepared commercially by the application of electrolysis: (i) Name the: I. Electrolyte used in the process: (i) Aluminium oxide/(Molten) alumina. II. Bauxite. III. Carbon electrodes/graphite electrodes. (ii) Reasons why cryolite, NaAl F\(_6\) is added to the electrolyte: –As a solvent. –Helps reduce the melting point of alumina (Al\(_2\)O\(_3\)). –To increase the conductivity of electrolyte. (c)(i) Gaseous fuels produced from coke: –Producer gas. –Water gas. (c)(ii) Water gas. (iii) Reason for your answer in(c)(ii): The producer gas contains about 67%/More non-combustible nitrogen and 33% less combustible carbon (II) oxide while water gas contains equal amount of combustible carbon (II) oxide and hydrogen. (iv) Balance equation for each production of gaseous fuel: Producer gas. 2C\(_{(s)}\) + O2\(_{2(g)}\) + 4N\(_{2(g)}\) --> 2CO\(_{(g)}\) +4N\(_{2(g)}\). Water gas: C\(_{(s)}\) + \(H_2\)O —> CO\(_{(g)}\) + H\(_{2(g)}\) (d)(i) What would be observed when: I. Chlorine gas is bubbled through aqueous sodium iodide. –Colourless solution turn reddish brown. II. Chlorine gas is passed over heated iron in a hard glass tube. –Grey silvery solid turns brown. III. Aqueous silver trioxonitrate (V) is added to aqueous sodium bromide. –Cream/(pale) yellow precipitate. (ii) Chemical equation for reactions in (d)(i): (i) Cl\(_2\) +2Nal ---> 2NaCl + l\(_2\) (ii) 2Fe +3C\(l_2\) —> 2FeC\(l_2\) (iii) AgN\(O_3\) +NaBr —> NaNO\(_3\) + AgBr.

(a) Define esterification: Esterification is the reaction between an alkanol and alkanoic/organic acid to produce an alkanoate/ester and water in the presence of mineral acid. (b) Properties ottitastic: —Good insulators to heat and electricity. —Can be recycled. —Are non-biodegradable. —Are durable.— can be tailor-made (to suit particular purpose). —Are resistant to corrosion/chemicals. —Can be remoulded. (c) Components of duralumin: —Aluminium, —Magnesium. —Copper. —Manganese. (d)(i) What is meant by raw material: Raw material is a starting material used in producing or manufacturing a substance/product. (ii) What is meant by primary product: This is the main product of the industry/an intermediate product that can be still converted to other usable product. (e) Charles' law: It states that the volume of a given mass of gas is directly proportional to its absolute temperature/ temperature in Kelvin if the pressure is constant. (f) Protective equipment in the laboratory: —Safety goggle. —Hand gloves. —Laboratory coat/apron. —Boots or safety boot. —Nose mask/shield. —Fume cupboard. --Respirator/ gas mask. —Fire extinguisher. (g) Uses of Ammonia: —As a refrigerant. —For electing aluminium. —As agent for manufacturing of fertilizer. —As solvent for removal of grease and oil stains. —For softening of temporarily hard water. —Use in making/manufacturing ammonium salt. —For treating insect bite. —As agent for manufacturing of HNO\(_3\). —As a precipitating agent for qualitative analysis. (h)(i) Process by which lighter hydrocarbons are obtained from heavier ones: —Cracking. (ii) Products:formed from the reaction between ethanol and sodium metal: —Sodium ethoxide + Hydrogen gas. (iii) Oxidation number of sulphur in H\(_2\)SO\(_4\) H\(_2\)SO\(_4\) = 2 x 1 + 5 + 4(-2) — 2 = 0 = 2 + 5 — 8 = 0 2 + 5 = 8 5 = 8 — 2 = 6 5 = 6 (j) IUPAC name of: (i) NaClO\(_3\) —>Soludium trioxochlorate(V). (ii) CUSO\(_4\)SH\(_2\)O —> Copper (II) tetraoxosulphate (VI) —> -pentahydrate

(a) Considering the following table. Element Atomic Number Mass Number J 9 19 Q 13 27 R 16 32 X 19 39 Y 24 52 (i) I. J is Halogen. II. Y is most likely to be attracted by magnet. III. X belongs to group I. IV. R wduld readily form an ion with a double negative charge. (ii) Type of bond that can exist between J and X when they combine: – Ionic/Electrovalent bond. (iii) Neutrons in Q – 14 (iv) Compound formed when R combines with X: – X\(_2\)R. (v) Element that exists as diatomic molecule: – Element J. (vi) D-block element of the periodic table: Element Y. (b)(i) Explain the term Atomic Orbital: This is a region/space within a principal energy level where there is high probability of finding an electron or an area where the electron lives. (ii) I. Postulates of Dalton's atomic theory: –Matters are made up of small indivisible particles called atoms. –Atom can neither be destroyed nor created. –Atoms of the same element are identical but different from atoms of other elements. –Atoms combine (to form compounds) in simple whole number ratio. II. Limitations of Dalton's Atomic Theory: –Atoms are divisible (protons neutrons and electrons). –Atoms can be created and destroyed (in nuclear reaction). –Existence of polymers (large) organic molecules. –Existence of isotopes. (iii) Structure of sodium chloride in solid state: Soldium chloride (Nacl) as an ionic solid compound exists in crystal lattic/face centred cube which is made up of positive and negative ions. (c) A sample of carbon is burnt at a rate of 0.50 g per second for 30 minutes to generate heat: (i) Balance equation for the reaction: C\(_{(s)}\) + O\(_{2(g)}\) -> CO\(_{2(g)}\) (ii) Determine the: I. Volume of carbon (IV) oxide produced at s.t.p. Mass of carbon burnt = 0.5 x 30 x 60 = 900 g from the reaction equation. 12 g of carbon at s.t.p produces 22.4 dm\(^3\) of CO\(_2\) 900 g of carbon = \(\frac{22.4}{12}\) x 900 = 1680 dm\(^3\) II. Moles of oxygen used up in the process at s.t.p. from the reaction equation: I mole of O\(^2\) used = 1 mol of CO\(_2\) produced. But 22.4 of O\(_2\) = 1 mole of O\(_2\). :. 1680 dm\(^3\) of O\(_2\) = \(\frac{1}{22.4}\) x 1680 = 75.0 mol OR Mol of O\(_2\) = \(\frac{900}{12}\) = 75.0 mol.

Hydrogen and carbon (ii) oxide will be formed when red steam is passed ever red-hot carbon. Option A,B,D are not produced through this process

(a) Burette reading Rough 1st titration 2nd titration Final Burret Reading (cm\(^3\)) 23.50 45.90 33.60 Initial Burret Reading (cm\(^3\)) 01.10 23.50 11.30 Volume of acid used (cm\(^3\)) 22.40 22.40 22.30 Average titre = \(\frac{22.40 + 22.40 + 22.30}{3}\) = 22.37 cm\(^3\) (b)(i) Conc. of B in mol dm\(^{-3}\) \(\frac{C_AV_A}{C_BV_B}\) = \(\frac{2}{I}\) C\(_B\) = \(\frac{C_AV_A}{2VB}\) = \(\frac{0.100 \times 22.37}{2 \times 25}\) = 0.0447 mol dm\(^{-3}\) (ii) Conc. of Na\(_2\)CO\(_3\) in Bg dm\(^{-3}\) Conc. of Na\(_2\)CO\(_3\) = 0.0447 x Molar Mass of B = 0.0447 x 106 = 4.74 g dm\(^{-3}\) (iii) 250 cm\(^3\) of B contained 2.50 g of Na\(_2\)CO\(_3\) 1000 cm\(^3\) of B = \(\frac{2.50 \times 1000}{250}\) = 10.0g mass conc of B = 10 g dm\(^{-3}\) % Na\(_2\)CO\(_3\) = \(\frac{4.74}{10} \times 100\) = 47.4%

(a)(i) Fountain experiment (ii) To demonstrate high solubility of hydrogen chloride gas (iii) Ammonia (iv) No colour/colourless (v) No (vi) The gases are highly soluble in water (b) U - CaO\(_3\)/Calcium trioxocarbonate (IV) V - CaO/Calcium oxide W - Ca(OH)\(_3\)/Calcium hydroxide/Lime water

TEST Observation Inference (a) C\(_{(s)}\) + H\(_2\)O + litmus paper Red litmus paper turned blue Alkaline/Basic solution (b)(i) E\(_{(aq)}\) + litmus paper Blue Litmus paper turned red Acidic solution (ii) E\(_{(aq)}\) + C\(_{(aq)}\) Effervescence occurred Colourless and odourless gas which turned water milky was evolved CO\(_2\) gas from HCO\(_3^-\)/CO\(_3^2\) (c)(i) D\(_{(s)}\) + H\(_2\)O D dissolved to give a colourless solution D is a soluble salt (ii) D\(_{(aq)}\) + BaCl\(_{2(aq)}\) + dil HCl(\(_{excess}\)) White precipitate Precipitate insoluble SO\(^{2-}\) or SO\(_3^{2-}\) or CO\(_3^2\) or SO\(_4^{2-}\) SO\(_4^{2-}\) present (iii) D\(_{(aq)}\) + NH\(_{3(aq)}\) in drops then in excess White gelatinous precipitate Precipitate dissolved Zn\(^{2+-}\) or AL\(^{3+}\) Zn\(^{2+-}\) confirmed

(a) Burette reading Rough 1st titration 2nd titration Final Burret Reading (cm\(^3\)) 23.50 45.90 33.60 Initial Burret Reading (cm\(^3\)) 01.10 23.50 11.30 Volume of acid used (cm\(^3\)) 22.40 22.40 22.30 Average titre = \(\frac{22.40 + 22.40 + 22.30}{3}\) = 22.37 cm\(^3\) (b)(i) Conc. of B in mol dm\(^{-3}\) \(\frac{C_AV_A}{C_BV_B}\) = \(\frac{2}{I}\) C\(_B\) = \(\frac{C_AV_A}{2VB}\) = \(\frac{0.100 \times 22.37}{2 \times 25}\) = 0.0447 mol dm\(^{-3}\) (ii) Conc. of Na\(_2\)CO\(_3\) in Bg dm\(^{-3}\) Conc. of Na\(_2\)CO\(_3\) = 0.0447 x Molar Mass of B = 0.0447 x 106 = 4.74 g dm\(^{-3}\) (iii) 250 cm\(^3\) of B contained 2.50 g of Na\(_2\)CO\(_3\) 1000 cm\(^3\) of B = \(\frac{2.50 \times 1000}{250}\) = 10.0g mass conc of B = 10 g dm\(^{-3}\) % Na\(_2\)CO\(_3\) = \(\frac{4.74}{10} \times 100\) = 47.4%

In chapter one, page 1, Jimi asked Wole because he knew that his father was going to be mad seeing Wole after what he did (almost making his father) bankrupt.

Rites; is a religious or other solemn ceremony or act.

While entering Mr Mallum’s office, Jimi and Seyi Lawal met two persons coming out of the principal’s office, they were Efua and her mother. The others in the options were not present at the time of the event See page 9-10