RVHS Prelim P2_QP

1 River Valley High School 9729/02 [Turn over 2018 Preliminary Examinations RIVER VALLEY HIGH SCHOOL YEAR 6 PRELIMINARY EXAMINATION CANDIDATE NAME CLASS CENTRE NUMBER S 3 0 4 4 INDEX NUMBER H2 CHEMISTRY 9729/02 Paper 2 Structured Questions 12 Sep 2018 2 hours Additional Materials: Data Booklet READ THESE INSTRUCTIONS FIRST. DO NOT OPEN THIS BOOKLET UNTIL YOU ARE TOLD TO DO SO. Write your name, class and index number in the spaces at the top of this page. Write in dark blue or black pen. You may use an HB pencil for any diagrams or graphs. Do not use staples, paper clips, highlighters, glue or correction fluid. Answer all questions in the spaces provided on the Question Paper. The use of an approved scientific calculator is expected, where appropriate. A Data Booklet is provided. The number of marks is given in brackets [ ] at the end of each question or part question. PAPER 2 QUESTION 1 9 QUESTION 2 9 QUESTION 3 8 QUESTION 4 14 QUESTION 5 12 QUESTION 6 10 QUESTION 7 13 Units s.f. PAPER 1 PAPER 2 PAPER 3 TOTAL PAPER 4 GRADE 30 75 80 185 55 This paper consists of 20 printed pages.

2 River Valley High School 9729/02 [Turn over 2018 Preliminary Examinations Answer all questions in the spaces provided. 1 Magnesium, aluminium, W and X are 4 different elements in the 3 rd Period. The following are some of their properties: The chloride of W dissolves in water to give a strongly acidic solution and the oxide of W. The chloride of X reacts with ethanoic acid to fo rm ethanoyl chloride as one of the products. (a) Identify the elements, W and X, and write the balanc ed equations for the reactions described above. W: ………………………… Chloride of W dissolved in water (equation): ……………………………………………………………………………………… X: ………………………… Chloride of X reacting with ethanoic acid (equation): ……………………………………………………………………………………… [2] (b) Aluminium oxide is a white solid that is soluble in NaOH(aq) to give a colourless solution. ( i ) Write a balanced equation, with st ate symbols, to describe the reaction of aluminium oxide with NaOH(aq). ……………………………………………………………………………………… [1]

3 River Valley High School 9729/02 [Turn over 2018 Preliminary Examinations ( i i ) Describe the observations made when HC l(aq) is carefully added to this colourless solution, until HCl(aq) is in excess. ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… [2] (c) State and explain how the decom position temperature of BaCO 3 compares with that of MgCO3. ………………………………………………………………………………………... ………………………………………………………………………………………... ………………………………………………………………………………………... ………………………………………………………………………………………... ………………………………………………………………………………………... ………………………………………………………………………………………... [3] (d) Explain why the 1 st ionisation energy of aluminium is of lower magnitude compared to that of magnesi