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(a)(i) Functional group is a bond, an atom or group of atoms which give an organic compound its characteristic chemical properties. (ii) Alkanol or hydroxyl or alkanoate. (b)(i) Cyclopropane. (ii) 2C\(_3\)H\(_6\) + O\(_6\) + O\(_2\) —> 6CO\(_2\) + H\(_2\)O. (iii) Substitution reaction. (iv) (c)(i) Sample A – Alkene. Sample B - Alkyne. Sample C – Alkanol. Sample D – Alkanoic acid. (ii) Both samples A and B are unsaturated compounds. (iii) Sample B is a terminal alkyne. (iv) Esterification. (v) As a catalyst. (vi) To remove water. (d)(i) The organic waste is fed into a biodigester where different kinds of bacteria convert the decaying matter into biogas CH\(_4\) / CO\(_2\) / H\(_2\) / CO through the process of anaerobic decomposition. (ii) (I) For cooking / Fuel. (2) For • heating / Fuel (3) For lighting / Fuel (3) As residue for fertilizer (4) Generating electricity.

(a)(i) Burette Reading (cm\(^3\) Rough Titration (cm\(^3\) 1st 2nd Titration (cm\(^3\) 2nd Titration Final Burette Reading (cm\(^3\)) Initial Burette Reading (cm\(^3\)) Vol. of Acid Used (cm\(^3\)) 21.00 4.00 17.00 38.50 21.00 17.50 23.30 5.70 17.60 Average Titre = \(\frac{17.50 + 17.60}{2}\) = 17.55 cm\(^3\) (b)(i) Na\(_2\)CO\(_{3(aq)}\) + 2HCl\(_{(aq)}\) \(\to\) 2NaCl\(_{(aq)}\) + H\(_2\)O\(_{(l)}\) + CO\(_{2(g)}\) Molar mass (Na\(_2\)CO\(_3\)) = (2 x 23) + 12 + (3 x 15) = 106 gmol\(^{-1}\) 250cm\(^3\) of solution contained 2.45g of Na\(_2\)CO\(_3\) 1000cm\(^3\) of solution contained = \(\frac{2.45 \times 1000}{250}\) = 2.45 x 4 = 9.80g Con. B (Na\(_2\)CO\(_3\)) = \(\frac{9.80}{106}\) = 0.0925 mol dm\(^{-3}\) (ii) Conc. of A in mol dm\(^{-3}\) \(\frac{C_AV_A}{C_BV_B} = \frac{N_A}{N_B}\) \(\frac{C_A \times 17.55}{0.0925 \times 25}\) = \(\frac{2}{1}\) C\(_A = \frac{0.0925 \times 25 \times 2}{17.55}\) = 0.264 mol dm\(^{-3}\) (iii) Conc. of A in gdm\(^{-1}\) Molar mass HCl = 1 + 35.5 = 36.5 g mol\(^{1}\) Conc of A(gdm\(^{-3}\)) = 0.264 x 36.5 = 9.64 gdm\(^{-1}\) (iv) volume of the gas evolved 1 mole of Na\(_2\)CO\(_3\) = 1 mole of CO\(_2\) at s.t.p n(CO\(_2\)) = n(NaCO\(_3\)) = 0.092.5 mole vol. of CO\(_2\) = n x volume = 0.0925 x 22.4 dm\(^{-3}\) = 2.07dm\(^3\) at s.t.p Volume of CO\(_2\) liberated in 23 cm\(^3\) of Na\(_2\)O\(_3\) will be \(\frac{2.07 \times 25}{1000}\) = 0.0518 dm\(^3\) or 51.8 cm\(^3\) at s.t.p

(i) P - Delivery tube Q - Drying tower R - Calcium oxide S - Ammonia gas T - Retort stand with clamp (ii) Upward delivery of gas/downward displacement of air (iii) To dry the gas (iv) Ca(OH)\(_{2(aq)}\) + 2NH\(_4\)Cl\(_{(aq)}\) \(\to\) CaCl\(_{2(aq)}\) + 2H\(_2\)O\(_{(l)}\) + 2NH\(_{3(g)}\)

TEST OBSERVATION INFERENCE (i) C(\(_{aq}\)) + AgNO\(_3\) + HNO\(_{3(aq)}\) + NH\(_{3(aq)}\) excess White precipitate formed precipitate insoluble Precipitate soluble/dissolved Cl\(^-\) or S\(^{2-}\) or CO\(_3^{2-}\) Cl\(^-\) present (ii) C\(_{(aq)}\) + HCl\(_{(aq)}\) + BaCl\(_{2(aq)}\) No visible reaction/no gas evolved White (chalky) precipitate formed SO\(_4^{2-}\) present (iii) C\(_{(aq)}\) + NaOH\(_{(aq)}\) in drops in excess Mixed warmed White gelatinous precipitate White precipitate dissolved/soluble Colourless gas evolved pungent/choking/irritating smell evolved Gas turns red litmus paper blue or forms dense white fumes with conc. HCl Zn\(^{2+}\) or Al\(^{3+}\) suspected Zn\(^{2+}\) or Al\(^{3+}\) suspected NH\(_3\) gas evolved NH\(_4^+\) present (iv) C\(_{(aq)}\) + NH\(_{3(aq)}\) in drops in excess White gelatinous precipitate Precipitate dissolved/soluble Zn\(^{2+}\) or Al\(^{3+}\) is suspected Zn\(^{2+}\) present

(a)(i) Burette Reading (cm\(^3\) Rough Titration (cm\(^3\) 1st 2nd Titration (cm\(^3\) 2nd Titration Final Burette Reading (cm\(^3\)) Initial Burette Reading (cm\(^3\)) Vol. of Acid Used (cm\(^3\)) 21.00 4.00 17.00 38.50 21.00 17.50 23.30 5.70 17.60 Average Titre = \(\frac{17.50 + 17.60}{2}\) = 17.55 cm\(^3\) (b)(i) Na\(_2\)CO\(_{3(aq)}\) + 2HCl\(_{(aq)}\) \(\to\) 2NaCl\(_{(aq)}\) + H\(_2\)O\(_{(l)}\) + CO\(_{2(g)}\) Molar mass (Na\(_2\)CO\(_3\)) = (2 x 23) + 12 + (3 x 15) = 106 gmol\(^{-1}\) 250cm\(^3\) of solution contained 2.45g of Na\(_2\)CO\(_3\) 1000cm\(^3\) of solution contained = \(\frac{2.45 \times 1000}{250}\) = 2.45 x 4 = 9.80g Con. B (Na\(_2\)CO\(_3\)) = \(\frac{9.80}{106}\) = 0.0925 mol dm\(^{-3}\) (ii) Conc. of A in mol dm\(^{-3}\) \(\frac{C_AV_A}{C_BV_B} = \frac{N_A}{N_B}\) \(\frac{C_A \times 17.55}{0.0925 \times 25}\) = \(\frac{2}{1}\) C\(_A = \frac{0.0925 \times 25 \times 2}{17.55}\) = 0.264 mol dm\(^{-3}\) (iii) Conc. of A in gdm\(^{-1}\) Molar mass HCl = 1 + 35.5 = 36.5 g mol\(^{1}\) Conc of A(gdm\(^{-3}\)) = 0.264 x 36.5 = 9.64 gdm\(^{-1}\) (iv) volume of the gas evolved 1 mole of Na\(_2\)CO\(_3\) = 1 mole of CO\(_2\) at s.t.p n(CO\(_2\)) = n(NaCO\(_3\)) = 0.092.5 mole vol. of CO\(_2\) = n x volume = 0.0925 x 22.4 dm\(^{-3}\) = 2.07dm\(^3\) at s.t.p Volume of CO\(_2\) liberated in 23 cm\(^3\) of Na\(_2\)O\(_3\) will be \(\frac{2.07 \times 25}{1000}\) = 0.0518 dm\(^3\) or 51.8 cm\(^3\) at s.t.p

A drop in the ocean; a very small amount compared with what is needed or expected.

farm out; to give work to other people to do. To place one's child in someone else's care.

When pigs fly" is an adynaton, a way of saying that something will never happen.

If you are caught between a rock and a hard place, you are in a difficult situation where you have to choose between two equally unpleasant courses of action.

If someone is like a bear with a sore head, they are being very bad-tempered and irritable. grumpy; bad-tempered and irritable

Bumpy ride; to have a difficult time

If Adeola wishes to go to the farm, he is free to

Take (one's) eye off the ball. To fail to remain focused on or motivated about some goal, objective, or matter at hand.

Hedge in; to form a boundary around (something). to surround or restrict (someone) in a way that prevents free movement or action

(from) hand to mouth; satisfying only one's immediate needs because of lack of money for future plans and investments.