2021_RVHS_Prelim_P2_Qns

River Valley High School 2021/8873/02 [Turn over 2021 JC 2 Preliminary Examination Paper 2 RIVER VALLEY HIGH SCHOOL JC 2 PRELIMINARY EXAMINATION CANDIDATE NAME CLASS 2 0 J CENTRE NUMBER S INDEX NUMBER H1 CHEMISTRY 8873/02 Paper 2 Structured Questions 15 Sep 2021 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 pencil for any diagrams or graphs. Do not use staples, paper clips, highlighters, glue or correction fluid. Section A Answer all questions in the space provided. Section B Answer one question in the space provided. A Data Booklet is provided. Do NOT write anything on it. The number of marks is given in brackets [ ] at the end of each question or part question. For Examiner’s Use Paper 1 30 Paper 2 1 9 2 7 3 6 4 5 5 18 6 15 7 20 8 20 s.f. units Paper 2 80 Total 110 This paper consists of 20 printed pages.

2 River Valley High School 2021/8873/02 2021 JC 2 Preliminary Examination Paper 2 Section A (60 marks) Answer all the questions in this section. 1 (a) (i) Describe the reactions, if any, of the chlorides MgC l2 and PCl5 with water. Write equations for all reactions that occur, and suggest the pH of the resulting solutions. Relate the reactivity of the se chlorides to their structure and bonding. ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… [3] (ii) Carbon is in the same group as silicon. Suggest and explain if CC l4 will react with water. ……………………………………………………………………………… ……………………………………………………………………………… [1] (b) Phosphorus exist as 31P, 32P and 33P isotopes. 31P is the most stable isotopes. (i) Define the term isotopes. ……………………………………………………………………………… ……………………………………………………………………………… [1]

3 River Valley High School 2021/8873/02 [Turn over 2021 JC 2 Preliminary Examination Paper 2 (ii) 31P can react with chlorine to form phosphorus chloride. Phosphorus in phosphorus chloride can exhibit variable oxidation states. Based on your knowledge in periodicity, state the two common oxidation states of phosphorus in phosphorus chloride ……………………………………………………………………………… [1] (iii) Phosphorus can exist as cations or anions. The angle of deflection for a beam of 31P+ ions in an electric field is 6. Calculate the angle of deflection for a beam of 33P3 ions in the same electric field and show in the diagram below, Fig 1, how