CHEMISTRY JC2 Preliminary Examination Paper 1 Multiple Choice Additional Materials: Data Booklet Optical Mark Sheet (OMS) 9647/01 23 August 2011 1 hour
READ THESE INSTRUCTIONS FIRST On the separate multiple choice OMS given, write your name, FIN/NRIC and class in the spaces provided. Shade correctly your class and FIN/NRIC number. Eg. If your NRIC is S9306660Z, shade S9306660Z for the item “index number”. There are forty questions in 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 using a soft pencil on the separate OMS. Each correct answer will score one mark. A mark will not be deducted for a …show more content…
A diagram of the voltaic pile is shown below:
Blotting paper soaked in Zinc metal H2SO4 (aq) Copper metal
One cell
Which of the following statement(s) is/are correct? 1 2 3 The overall equation of the reaction occurring in the cell is Cu2+ + Zn Zn2+ + Cu. Zinc is the anode, while copper is the cathode. cathode The e.m.f. of the voltaic pile can be increased by stacking more elements
37
When drops of NaOH (aq) were added to a green solution of Cr(NO3)3 (aq), a greygreen precipitate was formed. The precipitate dissolved when excess NaOH(aq) was added, forming a dark green solution. Subsequent additions of liquid ammonia caused the solution to turn violet. According to the information given above, which of the following statement(s) is/are incorrect? 1 2 3 OH− acted as a ligand in the first addition of drops of NaOH (aq). NH3 is a stronger field ligand as compared to OH−. The [Cr(H2O)6]3+ complex is the most unstable of all the complexes involved.
SRJC
9647 / 01 / Prelim / 2011
[Turn Over
19