2016 HCI H1 Chemistry Prelims P1 Questions

HWA CHONG INSTITUTION C2 Preliminary Examinations Higher 1 CANDIDATE NAME CT GROUP 15S CENTRE NUMBER INDEX NUMBER CHEMISTRY Paper 1 Multiple Choice Additional Materials: Optical Mark Sheet (OMS) Data Booklet 8872/01 21 September 2016 50 min READ THESE INSTRUCTIONS FIRST Write in soft pencil. Complete the information on the optical mark sheet (OMS) as shown below. There are thirty 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 OMS. 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 question booklet consists of 9 printed pages. Write your name Write and shade your NRIC or FIN number Write your CT group

2 HCI 8872/01 P1 Prelim 2016 SECTION A 1 How many neutrons are present in 0.13 g of 13C? [L = the Avogadro constant] A 0.06 L B 0.07 L C 0.13 L D 0.91 L 2 A protonated oxoanion of vanadium has been characterised at pH 3 with the formula HV10O285r . Which oxoanion contains vanadium in a different oxidation state from that shown in HV10O285r ? A VO2+ B VO2+ C V4O124r D VO3r 3 The double salt (NH4)2SO4.FeSO4.6H2O is used as a standard in volumetric analysis for titrations with oxidising agents. What is the electronic configuration of the metal ion in this salt? A [Ar]4s23d6 B [Ar]4s23d4 C [Ar]3d6 D [Ar]3d5 4 The table shows the successive ionisation energies for an element Q. 1st 2nd 3rd 4th Ionisation energy / kJ mol-1 418 3070 4600 5860 What is the likely formula of the oxide of Q? A QO B Q3O2 C Q2O D Q2O3 5 Which statement about an element in the Periodic Table is correct? A Magnesium is a metalloid, has a giant structure and is a good conductor of electricity B Silicon is a metalloid, has a simple molecular structure and is a semi-conductor of electricity. C Sodium is a metal, has a giant structure and is a good conductor of electricity. D Sulfur is a non-metal, has a giant structure and is a poor conductor of electricity

3 HCI 8872/01 P1 Prelim 2016 6 The metal niobium, Nb, has a relative atomic mass of 92.9 and is used in various stainless steel alloys. It is made by reducing niobium chloride with sodium. In this reaction, 54.08 g of niobium chloride produces 18.58 g of niobium. What is the formula of the niobium chloride used? A NbCl2 B NbCl3 C NbCl4 D NbCl5 7 Which statement about bond formation is not correct? A A triple bond consists of one σ bond and two π bonds. B A π bond restricts rotation about the σ bond axis. C Bonds formed from atomic s orbitals are always σ bonds. D End-to-end orbital overlap results in a bond with electron density above and be