2023 NJC H2 Chem Prelim P1 (QP)

1 NJC SH2 Preliminary Examination 9729/01/23 [Turn over NATIONAL JUNIOR COLLEGE SH2 PRELIMINARY EXAMINATION Higher 2 CANDIDATE NAME SUBJECT CLASS REGISTRATION NUMBER CHEMISTRY Paper 1 Multiple Choice Additional Materials: Optical Answer Sheet Data Booklet 9729/01 14 September 2023 1 hour READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, 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 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 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. A Data Booklet is provided. Instructions on how to fill in the Optical Mark Sheet 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. Example: Student Examples of Registration No. Shade: 2205648 25648 This document consists of 8 printed pages.

2 NJC SH2 Preliminary Examination 9729/01/23 1 Use of the Data Booklet is relevant to this question. Which particle has more protons than electrons and more protons than neutrons? (D = H1 2 ) A D3O+ B H3O+ C NH2− D OD− 2 Cl2 reacts with hot dilute NaOH to give Cl− and ClOx− in a 5:1 ratio. What is the value of x in ClOx−? A 1 B 2 C 3 D 5 3 The boiling point of water (100 C) is greater than that of HF (20 C). Which statement is a correct explanation of this? A Each hydrogen bond formed between water molecules is stronger than that formed between HF molecules. B There are more atoms in a water molecule than there are in an HF molecule, resulting in stronger intermolecular forces in water. C There are on average, more hydrogen bonds between water molecules than there are between HF molecules. D The water molecule has stronger permanent dipole-permanent dipole interactions than the HF molecule. 4 When the carbon-oxygen bonds in methanol, CH3OH, methanal, HCHO, and methanoate, HCO2– are arranged in order of increasing length, what is the correct order? A CH3OH, HCO2–, HCHO B HCO2–,CH3OH, HCHO C HCHO, HCO2–,CH3OH D HCO2–, HCHO, CH3OH

3 NJC SH2 Preliminary Examination 9729/01/23 [Turn over 5 Histamine is produced in the body to help fight infection. Its shape allows it to fit into receptors which expand blood vessels. What are the bond angl