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Volume of pipette (G) = 25.00cm\(^3\) (a) The average volume of F used = 24.80cm\(^3\) (b)(i) Molar mass of NaOH = 40g/mol Given that solution G contains 1.00g of NaOH in 250cm\(^3\) of solution = 4.00g in 1000cm\(^3\) of solution molar concentration of G \(\frac{4}{40}\) = 0.100 mol. dm\(^{-3}\) (ii) The equation of the reaction is H\(_2\)CX\(_{(aq)}\) + 2NaOH\(_{(aq)}\) + 2H\(_2\)O \(\frac{\text{concentration of F x volume of F}}{\text{concentration of G x volume of G}}\) = mole ratio of \(\frac{F}{G}\) \(\frac{C_1 \times 24.80}{0.100 \times 25.00}\) = \(\frac{1}{2}\) C\(_1\) = \(\frac{0.100 \times 25.00}{24.80 \times 2}\) C\(_1\) = 0.0504m concentration of F = 0.504 mol dm\(^{-3}\) (iii) Molar mass of H\(_2\)X\(_3\) Given that 1000cm\(^3\) 1000 cm\(^3\) of solution of F \(\to\) 0.485 of acid 1000cm\(^3\) of sol. of F \(\to\) 485 x \(\frac{100}{10}\) = 4.85g/dm\(^3\) Molar mass of H\(_2\)X = \(\frac{\text{mass concentration}}{molarity}\) \(\frac{4.85 g/dm^3}{0.050mol/dm^{-3}}\) = 96 gmol\(^{-1}\)

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 C.

(a) Gasses denser than air can be collected by upward displacement of air or downward delivery. (b) Hydrogen chloride and ammonia are restively used to person the fountain experiment because of their high solubility in water

(a) The main ore of tin is cassiterite or tin stone, (SnO\(_2\)) (b) SnO\(_{(s)}\) + 2C\(_{(s)}\) \(\to\) Sn\(_{(l)}\) + 2CO\(_{(g)}\) (c) Bronze (Cu and Sn); Soldier (Pb and Sn)

(a) The Rhombic (Octahedral) Sulphur is the stable allotrope at room temperature. (b)(i) Petroleum crude oil (ii) Air pollution.

(a)(i) Dilute tetraoxosulphate (VI) acid i.e H\(_2\)SO\(_4\); (b)(i) Salt bridge (ii) Copper metal is the cathode in the Zinc - Zn\(^{2+}\) voltaic cell. (iii) Specially prepared platinum electrode over which hydrogen gas is bubbled

(a) Grind the magnesium ribbon into powder to increase its surface area which increases the rate of reaction Increase in the concentration of the copper will increase the rate of reaction. At lower than room temperature at catalyst can be applied to increase the rate of reaction. (b) Mg\(_{(s)}\) + 2HCI\(_{(aq)}\) --> MgCl\(_{2(aq)}\) + H\(_{2(g)}\) .

(a) An example of naturally occurring acid is the ethanoic acid (CH\(_3\)COOH) (b) If 0.5 mole of the mono-alkanoic acid weighs 44g 1 mole of the acid will weigh 2 x 44 = 88g. i.e. (CH\(_2\)) x + 45 = 88 (CH\(_2\)) X = 88 - 45 = 43; (14) x = 43 x = \(\frac{43}{14}\) = 3 3(CH\(_2\)) = \(C_3H_{6 +1}COOH = C_3H_7COOH\) The monoalkanoic acid is butanoic acid.

(a)(i) B\(_2\)A (ii) B and C are the elemems belonging to S-block of the Periodic Table because their outermost I electrons are just filled in S-sub energy level. (b) Calcium, Oxygen, Chlorine

a)(i) Caesium(Cs) (ii) Gold (Au) (b) Solution Y has been oxidized to iron (III) salts and it will give a reddish brown precipitate with excess sodium hydroxide.

(a) Acid salt is the salt which contains acidic hydrogen e.g. Sodium hydrogen trioxocarbonate (IV) (NaHCO\(_3\)) (b) Glass is not attacked by the concentrated trioxonitrate (V) acid

(a)(i) Fructose (ii) Starch is converted to glucose by enzymatic hydrolysis of the starch. (b)(i) Carbonyl group and the alkanol functional group (ii) It is the alkanol group that reacts with warm Fehling's solution.

(a)(i) Electrovalent compounds Convalent convounds The compound is made up of an aggregate of ions of opposite charges. Can conduct electricity as electrolyte. Can dissolve in water. Made up of molecules Cannot conduct electricity Can only dissolve in organic solvents such as ether. (ii) Coordinate or the active bond. (b)(i) The principal quantum number, angular momentum quantum number, Magnetic Orbital quantum number and magnetic spin quantum number. (ii) The 2 p-orbital group 3A and period two (c)(i) The measure of the degree of disorderliness or randomness of a chemical system. (ii) \(\Delta\) G = \(\Delta\) H - T\(\Delta\) S = -710 - 300(0.15) = -710 - 45 = -755 KJ/mol (iii) The reaction is spontaneou because \(\Delta\) G is negative.

(a)(i) Amino acids (ii) Soap + glycerol (b)(i) Cracking process. Conversion of the less demanded fractions to the more demanded in oil industry. (ii) The pieces of broken pot is to avoid local heating and therefore create medium of uniform heating. (iii) X is an alkene and will decolourize the reddish-brown colour of bromine vapour which methane cannot do. (v) Laboratory preparation of ethene. (c)(i) Effervescence occurs and hydrogen gas is evolved. 2CH\(_3\)CH\(_2\)CH\(_2\)OH + 2Na\(_{(S)}\) \(\to\) H\(_{2(s)}\) + 2CH\(_3\)CH\(_2\)CH\(_2\)ONa (ii) Propan-1-ol and propan-2-one respectively. The process involved in the reaction is oxidation of alkanols.