ACJC 2022 Prelim P1 QP

3 © ACJC 2022 9729/01/Prelim/2022 [Turn over 1 Which species deflects the most in an electric field? A 7Li+ B 24Mg2+ C 32S2− D 27Al3+ 2 The shape of each p-orbital is represented as two lobes. How many 3d orbitals have four lobes? A 2 B 3 C 4 D 5 3 Which species has the greatest number of unpaired electrons in its ground state? A Cu+ B CH3− C Mg D F 4 Which species contains a dative bond? 1 CO 2 NO3− 3 O3 A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 only

4 © ACJC 2022 9729/01/Prelim/2022 [Turn over 5 Which row correctly describes the shape and polarity of the species? species shape polarity A AlCl3 trigonal planar polar B SiF4 square planar non-polar C BrF3 trigonal pyramidal polar D BeCl2 linear non-polar 6 Which graph shows the behaviour of a fixed mass of an ideal gas at a constant temperature? A B C D 7 Which statements explain the difference in ionic radius between Na+ and F−? 1 Outermost electrons of F− experience weaker nuclear charge than those of Na+. 2 Outermost electrons of Na+ experience greater shielding effect than those of F−. 3 Outermost electrons of Na+ are nearer to the nucleus than those of F−. A 3 only B 1 and 2 only C 1 and 3 only D 1, 2 and 3 p ρ pV p pMr V p

5 © ACJC 2022 9729/01/Prelim/2022 [Turn over 8 0.1 mol of compound X dissolves in 1 dm3 of water to give a solution with a pH of 1. What is the identity of X? A AlCl3 B CH3COCl C NH4NO3 D CH3COOH 9 Wüstite, containing both Fe 2+ and Fe3+ ions, has the formula Fe 20Ox. Fe2+ constitutes 90% of the iron ions present in the compound. What is the value of x? A 18 B 19 C 21 D 22 10 Which option involves a positive entropy change? A the homolytic fission of gaseous chlorine B the lattice energy of sodium chloride C the contraction of an ideal gas at a constant temperature D cooling a copper strip from 373 K to 273 K

6 © ACJC 2022 9729/01/Prelim/2022 [Turn over 11 The reaction between NO and Br2 is proposed to proceed via the following mechanism: step 1: NO + Br2 NOBr2 (fast) step 2: NOBr2 + NO 2NOBr (slow) Which statements are correct? 1 NOBr2 is a radical. 2 The rate equation for this reaction is rate = k[Br2][NO]2. 3 NOBr2 is a transition state. A 1 and 2 only B 1, 2 and 3 C 1 and 3 only D 2 and 3 only 12 Which statement regarding catalysts is correct? A Catalysts change the ∆H value of a reaction. B Catalysts increase the yield of product in a reaction. C Catalysts provide a different mechanism for a reaction. D Catalysts change the Kc value of a reaction. 13 In aqueous solution, an equilibrium is established between chromate , CrO42− (yellow) and dichromate ions, Cr2O72− (orange). 2CrO42−(aq) + 2H+(aq) Cr2O72−(aq) + H2O(l) Which statement regarding the ions and the equilibrium is correct? A The oxidation number of chromium in both chromium-containing ions is different. B The difference in colour between CrO 42− and Cr 2O72− is due to a difference in energy gap between the 3d orbitals. C The Kc expression for the equilibrium is Kc = 2 2 7 2 2 2 + 2 4 [Cr O ][H O] [CrO ] [H ] − − . D Increasing the pH turns the solution yellow.

7 © ACJC 2022 9729/01/Prelim/2022 [Turn over 14 Nitrogen dioxide dimerises in a closed system and establishes the following equilibrium: 2NO2(g) N2O4(g) When 46.0 g of NO 2 was introduced into an evacuated rigid vessel with an initial pressure 2 atm at constant temperature, the apparent Mr value of the equilibrium mixture is 64.4. What is the Kp value of this equilibrium? A 0.281 B 0.556 C 0.778 D 1.11 15 Which solution will solid silver phosphate, Ag3PO4, be the least soluble in, at 25 °C? The numerical value of Ksp(Ag3PO4) is 8.89  10−17. A pure water B 2.0 mol dm−3 AgNO3(aq) C 2.0 mol dm−3 NH3(aq) D 2.0 mol dm−3 K3PO4(aq)

8 © ACJC 2022 9729/01/Prelim/2022 [Turn over 16 In an acid -base titration, 0.10 mol dm −3 solution of an acid is added to 25 cm 3 of 0.10 mol dm−3 solution of a base. The pH value of the solution is plotted against the volume, V, of acid added as shown in the diagram. Which statement is incorrect? A Maximum buffering capacity occurs at V = 12.5 cm3. B The pair of solutions could have been HCl(aq) and CH3NH2(aq). C Methyl orange is a suitable indicator for the above titration. D When the concentration of the acid is doubled, the pH at equivalence point remains unchanged.

9 © ACJC 2022 9729/01/Prelim/2022 [Turn over 17 Some vegetable oils contain ‘trans fats’ that are associated with undesirable increases in the amount of cholesterol in the blood. In the structures below, R1 and R2 are different saturated hydrocarbon chains. Which structure correctly illustrates an optically active ‘trans fat’? A B C D

10 © ACJC 2022 9729/01/Prelim/2022 [Turn over 18 A hydrocarbon reacted with bromine under suitable conditions to give the following product. What type of reaction occurred between the hydrocarbon and bromine? A electrophilic addition B free radical substitution C electrophilic substitution D nucleophilic addition 19 Ferulic acid is an antioxidant that occurs widely in plants. Assume that the CH3O− group is inert. ferulic acid Which statements about ferulic acid are correct? 1 It decolourises aqueous bromine. 2 It is not very soluble in water but dissolves in aqueous NaOH. 3 It can be prepared from using hot acidified K2Cr2O7 (aq). A 1 only B 1 and 2 only C 2 and 3 only D 1, 2 and 3

11 © ACJC 2022 9729/01/Prelim/2022 [Turn over 20 Unsaturated carbonyl compounds can undergo a useful reaction known as the Diels-Alder reaction with a diene. An example is shown below. C C C C H C H H O H C C CH2 CH2 CH CH2H H C O HCH2H CH2H + A student reacted the following diene and carbonyl compound together in a Diels-Alder reaction. C C CH2H3C CH2H O O CH2CH3 and Which product will not be formed? A O O CH2CH3 H3C C O O H3C CH3CH2 B O O CH3CH2 CH3 D O O CH3 CH2CH3

12 © ACJC 2022 9729/01/Prelim/2022 [Turn over 21 Deuterium, D, is a heavy isotope of hydrogen. Deuteriobenzene react s with chlorine and AlCl3 under controlled conditions so that only monochlorination takes place. Assuming that the carbon -deuterium bond is broken as easily as a carbon -hydrogen bond, wh at is the proportion of 2-chlorodeuteriobenzene in the mono-chlorinated products? A 16% B 20% C 33% D 40% 22 Two female sex hormones are oestrone and oestradiol. Which reagents could be used to distinguish between the two hormones? 1 SOCl2 2 2,4-dinitrophenylhydrazine 3 LiAlH4 in dry ether A 1 and 2 only B 1 only C