SAJC H1 CHEM P1 QNS

1 ST ANDREW’S JUNIOR COLLEGE JC2 Preliminary Examination Chemistry Higher 1 8872/01 Paper 1 Multiple Choice 19 September 2016 50 minutes Additional Materials: Multiple Choice Answer Sheet, Data Booklet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. There are 30 questions on this paper. Answer all questions. For each question there are four possible answers A, B, C and D. Choose the one you consider correct and record your choice in soft pencil on the separate Answer Sheet. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Any rough working should be done in this booklet. This document consists of 13 printed pages including this page.

2 Section A For each question there are four possible answers, A, B, C and D. Choose the one you consider to be correct. 1 Use of the Data Booklet is relevant to this question. How many carbon atoms are there in 11.5 g of ethanol? [L = Avogadro Constant] A 𝐿 4 B 𝐿 2 C L D 2L 2 Use of the Data Booklet is relevant to this question. CFC-150a is a molecule that is widely used as solvents for plastic, oils and fats as well as a fumigant in insecticide sprays. The percentage composition by mass of CFC-150a is: C, 24.2%; H, 4.1%; Cl, 71.2%. Which structural formula could be that of CFC-150a? A CH3Cl B CH2Cl2 C CH3CCl3 D CH2ClCH2Cl 3 When sodium iodide is added to concentrated sulfuric acid, the following reaction took place. NaI + H2SO4 HI + NaHSO4 (A) The hydrogen iodide produced would then react with concentrated sulfuric acid in the following series of reactions. 2HI + H2SO4 I2 + 2H2O + SO2 (B) 6HI + H2SO4 3I2 + 4H2O + S (C) 8HI + H2SO4 4I2 + 4H2O + H2S (D) Which of the above reaction shows the greatest change in oxidation number for sulfur?

3 4 Use of the Data Booklet is relevant to this question. P and Q are elements in the same period. P has more protons than Q. The 1st ionisation energy of P is lower than Q. P has one less unpaired electron than Q. What are the identities of P and Q? P Q A aluminium Magnesium B fluorine Boron C oxygen Nitrogen D sodium Silicon 5 Which solid has more than one type of chemical bond? A calcium nitrate B magnesium sulphide C Potassium D silicon dioxide 6 The diagram below shows the structure of compound R. compound R Which of the following set of bond angles are in compound R? A 90°, 120°, 180° B 105°, 109°, 120° C 105°, 107°, 120° D 107°, 109°, 180°

4 7 Consider the following four compounds with similar molecular mass. 1. CH3CH2CH2CH2CH3 2. C(CH3)4 3. CH3CH2COCH3 4. CH3CH2CH2CH2OH Which of the following statements about them is true? A The boiling points of the four compounds decrease from compound 4 >3 >2 >1. B The melting point of compound 1 and 2 are the same as they have the same molecular mass. C The predominant intermolecular force in compounds 3 and 4 are the same. D The predominant intermolecular force in compound 1 and 2 are the same. 8 The table shows the enthalpy change of neutralisation, ΔH, for various acids and bases. acid base ΔH / kJ nitric acid potassium hydroxide - 57.0 J potassium hydroxide - 55.0 nitric acid L - 52.0 M calcium hydroxide - 114.0 What are J, L and M? J L M A hydrochloric acid sodium hydroxide sulfuric acid B hydrochloric acid ethylamine hydrochloric acid C propanoic acid ethylamine sulfuric acid D propanoic acid sodium hydroxide hydrochloric acid

5 9 ClO2 is a yellow explosive gas that decomposes to form chlorine and oxygen gas. The equation for this decomposition is as follows: 2ClO2 Cl2 + 2O2 Given that the enthalpy change of the above reaction is +70 kJ mol -1, what is the enthalpy change of formation of ClO2? A - 140 kJ mol-1 B - 35 kJ mol-1 C + 35 kJ mol-1 D + 140 kJ mol-1 10 The rate equation for a reaction between E and F is rate = k[E][F]2 When the concentration of E was halved, what must be done to the concentration of F to make the reaction proceed at double of its former rate? A halve [F] B keep [F] constant C increase [F] by a factor of two D increase [F] by a factor of four 11 Which of the following graphs will not be a straight line? A concentration vs time graph for a first order reaction B concentration vs time graph for a zero order reaction C rate vs concentration graph for a first order reaction D rate vs concentration graph for a zero order reaction

6 12 When pressure is increased for a homogeneous gaseous system at equilibrium, the position of equilibrium shifted to the right. Which of the following could be the units of the equilibrium constant, Kc, for this system? A mol-1 dm3 B mol dm-3 C mol2 dm-6 D no units 13 What is the pH of the resultant solution when 50 cm 3 of 0.02 mol dm-3 HCl was mixed with 150 cm3 of 0.03 mol dm-3 HNO3? A 1.26 B 1.30 C 1.56 D 1.60 14 The table below show some data on two acid-base indicators. indicator approximate pH range of colour change colour change acid alkali bromocresol-green 3.8 – 5.5 yellow blue phenol-red 6.8 – 8.5 yellow red Which of the following shows the colour when these indicators were placed separately into a solution that has a [H+] = 1.00 x 10-6 mol dm-3? bromocresol-green phenol-red A blue red B blue yellow C yellow red D yellow yellow

7 15 Water can partially dissociate according to the following equation. Which of the following statements about water at 50°C is true? A More H+ ions will be produced, making water more acidic. B The concentration of OH- ions will be less than 1 x 10-7. C The pH of water will become less than 7. D The value of Kw will be less than 1 x 10-14. 16 Which of the following series does not have a decreasing trend? A atomic radius of P, S and Cl B electrical conductivity of Al, Si and P C ionic radius of Na+, Mg2+ and Al3+ D melting point of Si, P and S 17 Two unlabelled bottles in the laboratory either contains aluminium or silicon. A student proposed the following methods to distinguish them. 1. Heat both metals in excess oxygen gas, followed by aqueous acid to the residues. 2. Heat both metals in excess chlorine gas, followed by aqueous base to the residues. Which methods would enable the student to identify the metals? A 1 only B 2 only C 1 and 2 D neither 1 or 2. ΔH = +ve; Kw = 1 x 10-14 (25°C)

8 18 Carvone is responsible for the odour in spearmint. Carvone How many sp2 and sp3 hybridised carbons are there in Carvone? sp2 sp3 A 3 7 B 4 5 C 5 5 D 5 6 19 How many mono -chlorinated isomers can be formed when 1,3 -dimethylcyclohexane undergoes a reaction with limited chlorine and sunlight? A 3 B 4 C 5 D 6 20 What is the final organic product when butan-1-ol undergoes the following series of reactions?  Step 1: PCl5, room temperature  Step 2: ethanolic KOH, heat  Step 3: KMnO4, KOH(aq), heat A butanoic acid B propanoic acid C sodium butanoate D sodium propanoate

9 21 Compound G is an organic compound that contains carbon, hydrogen and chlorine. When 0.1 moles of compound G was heated with NaOH (aq), cooled and followed by the addition of excess AgNO3 (aq), 28.7 g of precipitate was obtained when the solution was filtered. What is the structure of compound G? A B C D 22 An alkene, H, of molecular formula C 5H10 undergoes vigorous oxidation to produce ethanoic acid and propanone. What is H? A 2-methylbut-1-ene B 2-methylbut-2-ene C pe