Sec_1_Science_SA2_St_Josephs_Convent_2018.pdf

lndex Number Class Name CHIJ ST JOSEPH'S CONVENT SEMESTRAL ASSESSMENT 2 o o sctENcE (cHEMTSTRY) Secondary 1 Express Friday, 5 October 201 8 50 minutes READ THESE INSTRUCTIONS FIRST Write your index number, class and name on all the work you hand in Write in dark blue or black pen. Do not use staples, paper clips, highlighters, glue or correction fluid. Section A There are ten questions. Answer all questions. For each question there are four possible answers A, B, C, and D. Choose the one you consider corect and shade your choice in the Multiple Choice Answer.Sheet with a 28 pencil. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Section B Answer all questions in the spaces provided The number of marks is given in brackets [] at the end of each question or part question Show all your workang on the same page as the rest of the answer. Omissron of essential working will result in loss of mirks. Electronic calculator may be used in this paper. The total of the marks for this paper is 40. A copy of the Periodic Table is printed on page 13 FOR EXAMINER'S USE A B 40 This document consists of !! printed pages Setter(s) : Mr Tan Keng Chiaw and Ms lzzati Jamil Sec 1 Erp Chemistry/SAzl8 [Turn Over I Total

2 1 Section A (10 marks) Answer all questions. "Amy drew a graph using the data she obtained from her experiments.,, Which step in the scientific inquiry process is the statement describing? analyzing results forming a hypothesis designing an experiment conducting an experiment Which of the following is the independent variable in this experiinent? the volume of air the color of the flame the height of the collar the location of the experiment An element is found to have the following properties . good electrical conductivity, .. shiny in appearance, . solid at room temperature. What is the element most likely to be? ' A boron B silicon C 'calcium D 'hydrogen Sec 1 Exp Chemrslry/SA2/1e 2 _ An experiment was conducted to investigate how the volume of air affects the colour' of the Bunsen burner flame. A B c D A B c D 3 4 w]ich of the forrowing statements best shows that coppe([) surfate sorution is amixture? A Copper(ll) sulfate solution is blue in colour. B Coppe(ll) sulfate is made up of different elements. C When heated, the water evaporates leaving a blue residue_ D No heat is released when coppe(ll) sulfate is dissolved in water.

5 3 Which of the underlined substance can be obtained through sublimation? salt from salt solution flour from flour suspension iodine from a mixture of iodine and salt water from a mixture of water and alcohol Two students carried out chromatography experiments to examine the dyes in a black ink. The chromatograms obtained by the students are shown below. solvent front They used the same black ink. Why are the chromatograms different? A One student did not use enough solvent. B The two students used different solvents. C The two students used different amount of black ink. D The solv