Year 12 HSC Chemistry Semester 1 Examination (April, 2010)
This examination contributes 15% towards your final assessment Time Allowed: 3 hours (plus 5 minutes reading time)
Student Number:________________________________________ Format of paper Part A: 20 multiple choice questions (worth 1 mark each). All answers must be entered in the special multiple choice Answer sheet provided.
Part B: Free response questions worth 80 marks in total. All answers must be written in the space provided. -A data sheet and Periodic table are provided at the back of this paper. Please detach for use.
Part A- 20 Multiple choice. (Worth one mark each) Allow about 45 minutes for this part. Answer questions on the Answer Sheet provided. 1. A polymer has the following properties and uses: • • • • low melting point transparent oil and water resistant uses include food packaging
Which one of the following polymers is consistent with the above description? (A) (B) (C) (D) 2. high density polyethene low density polyethene polychloroethene polyphenylethylene
A student was shown a demonstration in which a sample of an element was heated strongly in air, and the powder produced by the reaction was added to water. When tested with a pH probe connected to a data logger, the resulting solution had a pH of 9. Which one of the following elements could have been used? (A) (B) (C) (D) S C Si Ca
A few drops of bromine water are added to an unknown colourless hydrocarbon. No chemical change was observed after allowing the mixture to stand for 5 minutes under ordinary laboratory lighting. Which one of the following is the most appropriate conclusion? (A) (B) (C) (D) The hydrocarbon must be unsaturated. The hydrocarbon contains single bonds only. The hydrocarbon must contain a double bond. The hydrocarbon must contain a triple bond. 2
A student diluted a solution of a strong acid by mixing 10 mL with 90 mL of water. If the original solution had a pH of 2.1, what will the final pH of the solution be? (A) (B) (C) (D) 1.1 2.1 3.1 4.1
Consider the equilibrium reaction: C 6 H 5 COOH (aq) + H 2 O (l)
C 6 H 5 COO- (aq) + H 3 O+ (aq)
Which one of the following would decrease the C 6 H 5 COO- ion concentration in solution? (A) (B) (C) (D) 6. adding H 2 adding HCl adding NaOH adding C 6 H 5 COOH
Which one of the following is an acid/base conjugate pair? (A) (B) (C) (D) HCl/NaOH H 2 SO 4 /SO 4 2H 3 O+/H 2 O NH 2 +/NH 3
A piece of zinc is placed into copper(II) nitrate solution in a test tube.
Which one of the following changes would occur? (A) (B) (C) (D) The concentration of nitrate ions would decrease. The colour of the solution would darken. The concentration of nitrate ions would increase. The colour of the solution would fade.
The following monomer undergoes condensation polymerisation. H3C CH HO C O OH
What is the small molecule eliminated in this reaction? (A) (B) (C) (D) H2O CH 4 H2O2 CH 3 OH
Which of the following correctly identifies the low pH colour of each indicator? phenolphthalein (A) (B) (C) (D) pink pink colourless colourless methyl orange red yellow red red bromothymol blue yellow blue yellow blue
Which one of the following is least likely to be a stable isotope? (A) (B) (C) (D) hydrogen-3 boron-11 chlorine-35 potassium-39
What is the catalyst used to hydrate ethylene? (A) (B) (C) (D) zeolite yeast iron/iron oxide dilute sulfuric acid
Which of the following is true about current research into biopolymers? (A) (B) (C) (D) It has resulted in polymers which biodegrade when disposed of. It has resulted in the widespread adoption of biopolymers by industry. It has resulted in polymers less expensive than those from petrochemicals. It has resulted in polymers with exactly the same properties as those from petrochemicals.
Polyethene (polyethylene) is an extremely important polymer, available...