2024 Prelims NJC H2 Chem P3 (Ans)

1 NJC/H2 Chem Preliminary Examination/03/2024 [Turn over NATIONAL JUNIOR COLLEGE SH2 PRELIMINARY EXAMINATION Higher 2 CANDIDATE NAME SUBJECT CLASS REGISTRATION NUMBER CHEMISTRY Paper 3 Free Response Candidates answer on Question Paper. Additional Materials: Data Booklet 9729/03 17 September 2024 2 hours READ THE INSTRUCTIONS FIRST Write your subject class, registration number and name on all the work you hand in. Write in dark blue or black pen. You may use a soft pencil for any diagrams or graphs. Do not use staples, paper clips, glue or correction fluid. Section A Answer all questions. Section B Answer one question. A Data Booklet is provided. The use of an approved scientific calculator is expected, where appropriate. The number of marks is given in brackets [ ] at the end of each question or part question. For Examiner’s Use Section A 1 /20 2 /20 3 /20 Section B (*circle the question you attempted) 4 /20 5 /20 Paper 3 Total /80 This document consists of 32 printed pages.

2 NJC/H2 Chem Preliminary Examination/03/2024 Section A Answer all the questions in this section. 1 (a) Chlorinated phenols have seen growing applications as fungicides, herbicides, insecticides, and as starting materials in the production of various pesticides since the 1930s. It can be readily produced from compound A using chlorine in water. compound A (i) Write a balanced equation for the reaction between compound A and excess aqueous chlorine. [1] (ii) Compound A undergoes a series of reactions shown in the reaction scheme below. State the reagent and condition for Reaction I and II, and hence draw the structures of B and E. [4] (iii) Write a balanced equation for reaction III. [1] ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..………………

3 NJC/H2 Chem Preliminary Examination/03/2024 [Turn over ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… ………………………………………………………………………………..……………… …………………