HCI_H2 Prelim P1

HWA CHONG INSTITUTION C2 PRELIMINARY EXAMINATION 9746 H2 CHEMISTRY Paper 1 Multiple Choice 16 September 2008 1 hour READ THESE INSTRUCTIONS FIRST Complete the information on the optical mark sheet (OMS) as shown below. Write your CT group Write your name Write and shade your NRIC or FIN number There are 40 questions in 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 OMS. Each correct answer will score one mark. Marks will not be deducted for wrong answers. You should have a Data Booklet. You may use a calculator. Any rough working should be done in this booklet. This question booklet consists of 15 printed pages.

2 1 The Faraday constant was named after the British scientist, Michael Faraday, who contributed to the fields of electrochemistry and electromagnetism. Which expression correctly defines the Faraday constant? A the number of electrons carrying a charge of 9.65 × 104 C B the amount of charge carried by 500 cm3 of 2.0 mol dm−3 NaOH C the amount of charge required to liberate 1 g of hydrogen gas during electrolysis D the Avogadro constant divided by the electronic charge 2 In an experiment, 10 cm 3 of an organic compound in the gaseous state was sparked with excess oxygen. 20 cm 3 of carbon dioxide, 5 cm 3 of nitrogen and 35 cm 3 of steam were obtained among the products. All gas volumes were measured at the same temperature and pressure. What is the likely formula of the organic compound? A CH3CN B CH3CH2NH2 C CH3CH2CH2NH2 D H2NCH2CH2CH2CN 3 The variation in the second ionisation energy of six consecutive elements in the Periodic Table is shown in the graph. Which of these elements is a Group II element? A B C D 2nd ionisation energy / kJ mol−1 proton number 9746/01/HCI/C2 Prelim/2008

3 4 Hydrazine, N2H4, and hydrogen peroxide, H2O2, are both used as rocket propellants because they can produce large volumes of hot gases from a small volume of liquid. Which of the following statements about these two compounds is correct? A The bond angle in N2H4 is smaller than that in H2O2. B The N─H bond is shorter than the O─H bond. C The boiling point of N2H4 is lower than that of H2O2. D N2H4 is a weaker base than H2O2. 5 The value of pV is plotted against p for 2 gases, A and B, where p is the pressure and V is the volume of the gas. Which of the following could be the identities of the gases? gas A gas B A 0.5 mol of H2 at 25 ºC 0.5 mol of H2 at 50 ºC B 0.5 mol of H2 at 25 ºC 1 mol of SO2 at 25 ºC C 0.25 mol of SO2 at 25 ºC 0.5 mol of H2 at 25 ºC D 1 mol of SO2 at 25 ºC 0.5 mol of H2 at 25 ºC 6 Either carbon or carbon monoxide can bring about the reduction of iron( III) oxide in a blast furnace