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a. A transition element is one which has incompletely filled d-orbitals. bi. B ii. C c. Across a period(from left to right) there is a gradual increase in the number of protons in the nucleus/effective nuclear-charge. This increases the force of attraction between the nucleus and the electrons hence more energy is needed to remove the outermost electron. d. -methane -ethene -ethyne -ethanol -ethanoic acid e. -Alkanols are formed by replacing one hydrogen of water by an alkyl group -Alkyl groups have a positive inductive effect/ are electron releasing/electron donating -This increases the electron density of the oxygen f. -NaCl -CaCO3 -NH3 -C g. Geometric isomerism is the existence of two compounds with the same molecular formula but differ in the arrangement of groups attached to the carbon-containing double bond h. This is because constituents of water gases(CO and H2)are both combustible and give a higher calorific/heat value than producer gas i. It is defined as the heat change/released when 1 mole of a substance is burnt in excess oxygen. OR It is defined as the heat change/released when 1 mole of a substance is completely burnt in air ji. When the same quantity of electricity is passed through different electrolytes, the relative number of moles of the elements discharged is inversely proportional to the charges on the ions of the element. ii. 96500 C liberates 1.0 mol of Ag(s) 10920 C will liberate 10920/96500 =0.113 mole

ai. \(H_2SO_4 + 2NaOH → Na_2SO_4 + 2H_2O\) ii. Concentration of NaOH(\(C_n)\) \(C_n\) = 4/40= 0.1 mol/\(dm^3\) \(\frac{C_AV_A}{C_nV_n} = \frac{1}{2}\) \(C_A \times \frac{8}{0.1} \times 20 = \frac{1}{2}\) \(C_A =0.1 \times 20 \times \frac{1}{2} \times 8 = 0.125 mol /dm^3\) bi. -The volume of a gas is negligible compared to the total volume of the container -There are no forces of attraction or repulsion between molecules of the gas/collision between molecules is elastic. ii. The volume of a gas is not negligible because at high pressure the molecules occupy appreciable volume and at low temperature the intermolecular forces of attraction and repulsion become significant. ci. Glucose. ii. -Fructose -Galactose iii. hydrolysis iv. 2(\(C_6H_{10}O_5)_n + nH_2O → nC_{12}H_{12}O_{11}\) \(C_{12}H_{12}O_{11} + H_2O → 2C_6H_12O_6\) v. -maltase -diastase d. It Is the existence of compounds with the same molecular formula but different structural formulae/arrangement of the atoms/linkage of the atoms.

ai. %0 = 100 - (52.2+13.1) =34.7 C H O 52.2/12, 13.1/1, 34.7/16 4.35, 13.1, 2.168 4.35/2.168, 13.1/2.168, 2.168/2.168 2.00, 6.04, 1 empirical formula = \(C_2H_6O\) ii. 2 x vapour density = molecular mass 2x23=46 (\(C_2H_6O)_n\) = 46 [(12 x 2) + (1 x 6) + 16]n = 46 46n = 46 n = 1 molecular formula = \(C_2H_6O\) iii1. Hydroxyl iii2. b. 2(\(C_6H_{10}O_5)_n + nH_2O --diatase→ nC_{12}H_{22}O_{11}\) \(C_{12}H_{22}O_{11} + H_2O --maltase→ C_6H_{12}O_6 + C_6H_{12}O_6\) \(C_6H_{12}O_6 --zymase→ 2C_2H_5OH + 2CO_2\) ci. The reaction starts but the metal produces a layer of an oxide/aluminum oxide layer on its surface which is impermeable(to water) and stops the reaction. ii. Add dilute hydrochloric acid to excess aluminum filter off the excess metal leave the filtrate in a warm place/evaporate the filtrate to the point of crystallization/leave it in the sun. d. The flask is connected to the condenser and the solution is heated. The water vaporizes and is converted to(liquid)water in the condenser.

a. Water is added to the \(CaCl_2\): to form a solution. \(Na_2CO\), is then added to the solution to precipitate \(CaCO_3\),which is filtered, washed, and dried. b. Electricity is passed through a solution of CuSO4 using an impure copper as the anode and pure copper as the cathode. During electrolysis,the anode loses mass as copper dissolves and the cathode gains mass as copper is deposited. Anode: \(Cu_s → Cu^{2+}_{(aq)} + 2e^-\) Cathode: \(Cu^{2+}_{(aq)} + 2e^- → Cu_{(s)}\) ci. \(Cu_{(s)} + 4HNO_{3(aq)} →Cu(NO_3)_{2(aq)} + 2NO_{2(g)} + 2H_2O_{(l)}\) ii. -blue solution -(reddish)brown gas -gas bubbles/effervescence -metal dissolves/metal disappears iii. Because copper loses electrons/oxidation number increases. iv. Moles of acid=0.025x16= 0.4 mole Mole of \(NO_2\) = moles of acid/2 =0.2 mole Volume of gas (\(NO_2)\) at s.t.p. = 0.2 x 22.4 \(dm^{-3}\) = 4.48 mol \(dm^{-3}\) di. Pure HNO3 undergoes decomposition to \(NO_2\)(brown gas). This gas dissolves in the rest of the acid leaving it with that colour. ii. -2\(KNO_3 + H_2SO_4→K_2SO_4+2HNO_3\) - \(NaNO_3 + H_2SO_4→NaHSO_4 + HNO_3\)

ai. Iron dissolves readily in dilute \(H_2SO_4\) liberating hydrogen and forming \(FeSO_4\) while with Aluminum there is no reaction. ii. With aluminum there is no reaction(1)while iron dissolves in dilute \(HNO_3\) liberating hydrogen and forming \(Fe(NO_3)_2\) bi. \(S+O_2→SO_2\) ii. Vanadium(V) oxide/ platinized asbestos. iii. To favour the formation of more product/\(SO_3\). iv. The reaction is exothermic/high temperature favours the formation of more reactants/backward reaction. v. Catalysts are easily poisoned/easily damaged by dirt. vi. -SO2 damages buildings -damages living things -causes acid rain -irritates eyes, nose and throat -causes lung and respiratory diseases eg coughing, bronchitis, etc ci. Reagents -manganese(IV)oxide/MnO2 -concentrated HCI Conditions -heating Concentrated HCI(1) Bleaching powder/CaOCl2/KMnO4crystals Room temperature/heat is not required ii. -for bleaching wood pulp and textiles -for the production of plastics -for recovering of tin from its ore/extraction of tin -as a germicide and disinfectant/insecticide/in swimming pools -to sterilize/purification of water supply -for commercial manufacture of HCI -production of dyes and drugs -manufacture of solvents eg \(CCL_4\), \(CHCI_3\) di1. Hydrogen-fused calcium chloride/conc.tetraoxosulphate(VI)acid i2. Sulphur(IV)oxide-concentrated tetraoxosulphate(VI)acid/ anhydrous Calcium chloride i3. calcium oxide/ quick lime/silica gel ii1. copper and tin ii2. Copper and zinc

ai. \(H_2SO_4 + 2NaOH → Na_2SO_4 + 2H_2O\) ii. Concentration of NaOH(\(C_n)\) \(C_n\) = 4/40= 0.1 mol/\(dm^3\) \(\frac{C_AV_A}{C_nV_n} = \frac{1}{2}\) \(C_A \times \frac{8}{0.1} \times 20 = \frac{1}{2}\) \(C_A =0.1 \times 20 \times \frac{1}{2} \times 8 = 0.125 mol /dm^3\) bi. -The volume of a gas is negligible compared to the total volume of the container -There are no forces of attraction or repulsion between molecules of the gas/collision between molecules is elastic. ii. The volume of a gas is not negligible because at high pressure the molecules occupy appreciable volume and at low temperature the intermolecular forces of attraction and repulsion become significant. ci. Glucose. ii. -Fructose -Galactose iii. hydrolysis iv. 2(\(C_6H_{10}O_5)_n + nH_2O → nC_{12}H_{12}O_{11}\) \(C_{12}H_{12}O_{11} + H_2O → 2C_6H_12O_6\) v. -maltase -diastase d. It Is the existence of compounds with the same molecular formula but different structural formulae/arrangement of the atoms/linkage of the atoms.

The correct stress for the word 'cumulative' is on the first syllable, making 'CU-mu-la-tive' the correct option. In English, stress refers to the emphasis placed on certain syllables in words.

The correct stress for the word 'concessionaire' is 'con-cess-ion-AIRE'. The primary stress is on the last syllable.

The correct stress for the word 'horizontal' is 'hor-i-ZON-tal'. The primary stress is on the third syllable.

The correct stress for the word 'apathetic' is 'ap-a-THET-ic'. The primary stress is on the third syllable.

The correct stress for the word 'effeminate' is 'e-FFEM-i-nate'. The primary stress is on the second syllable.

Rhyming words are words that have the same ending sounds. The word 'fright' ends with the /aɪt/ sound. 'Height' rhymes with 'fright'.

The word 'high' rhymes with 'tie'. Rhyming words are words that have the same ending sound.

The word 'earn' rhymes with 'tern'. Rhyming words are words that have the same ending sound.

The word 'deer' rhymes with 'fear'. Rhyming words are words that have the same ending sound.