NJC 2018 SH1 H1 Promo Paper 1

1 NJC SH1 Promotional Examination 8873/01/18 [Turn Over NATIONAL JUNIOR COLLEGE SH1 PROMOTIONAL EXAMINATION Higher 1 CANDIDATE NAME SUBJECT CLASS REGISTRATION NUMBER CHEMISTRY Paper 1 Multiple Choice Additional Materials: Multiple Choice Answer Sheet Data Booklet 8873/01 Monday 1 October 2018 40 minutes READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. Write your name, subject class and registration number on the Answer Sheet in the spaces provided unless this has been done for you. There are 20 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. Read the instructions on the Answer Sheet very carefully. 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. The use of an approved scientific calculator is expected, where appropriate. This paper consists of 9 printed pages.

2 NJC SH1 Promotional Examination 8873/01/18 Instructions on how to fill in the Optical Mark Sheet Example: Shade the index number in a 5 digit format on the optical mark sheet: 2nd digit and the last 4 digits of the Registration Number. Student Examples of Registration No. Shade: 1805648 85648 SH1 CT CM G or IP B SH1 Promo cm1X

3 NJC SH1 Promotional Examination 8873/01/18 [Turn Over For each question there are four possible answers, A, B, C and D. Choose the one you consider to be correct. 1 The table shows the absolute abundance of a sample of naturally occurring isotopes of zinc. Absolute Abundance Zn30 64 100 Zn30 65 80 Zn30 67 20 Zn30 68 10 What is the relative atomic mass of this sample of zinc? A 64 B 64.9 C 68.1 D 72.2 2 Use of Data Booklet is relevant to this question. In research on the atomic nucleus, scientists have been comparing the stability of isotopes with the same neutron : proton ratio. Which isotope has the same neutron : proton ratio as 10B? A 32S B 32P C 40K D 40Ar 3 15 cm3 of a hydrocarbon was completely combusted in 75 cm 3 of oxygen. The final gaseous mixture contained 30 cm 3 of carbon dioxide and 30 cm 3 of unreacted oxygen. All gaseous volumes were measured under room temperature and pressure. What is the molecular formula of the hydrocarbon? A CH4 B C2H4 C C2H6 D C3H6 4 0.0050 mol of a metal oxide, Z2Ox, reacted exactly with 0.0060 mol of acidified potassium manganate(VII) solution. Given that the oxidation state of Z in the product is +6, what is the value of x?