RI 2015 A-Level H2 Chem Solution

This document is copyrighted, please do not reproduce it without permission © Raffles Institution Changes to 2015 H2 Chemistry A Level Question Paper Dear students, The TYS you have purchased is based on the 9647 (old) syllabus. You will be sitting for the 9729 (new) syllabus papers. This document will instruct you on the changes you need to make to the TYS questions. The Planning question for the 9729 syllabus will be in the Paper 4 (Practical). Some concepts are no longer tested in the 9729 syllabus and the values used for some calculations are now different (e.g. molar volume at s.t.p.) which will affect your choice of the answers. You are advised to make the changes on your question papers before you attempt it . Do inform your tutors if you notice any differences which were not highlighted in this document. ---------------------------------------------------------------------------------------------------------------------------------------------- Paper 1 15 Amend question “Which property generally increases down Group 2?” Amend Option D thermal stability of the carbonate Paper 2 3(d) Not in syllabus Paper 3 1(a)(ii) Amend question “How many chiral centres are there in the menthol molecule, and how many enantiomers are possible?” 2(b) Not in syllabus 3(a)(i) Not in syllabus 3(a)(ii) Not in syllabus - Reaction of calcium oxide with water 3(c)(i) - (ii) Not in syllabus 4(b) Bond energy of C=O in CO2 in the Data Booklet (for new syllabus) is the same as that given by the question 5(c)(ii) Amend question “Unlike other Group 1 carbonates, ….”

This document is copyrighted, please do not reproduce it without permission © Raffles Institution 2015 A - Level H2 Chemistry Paper 1 Suggested Solutions 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 B B C C B D B C A B D C D B D D A C B A 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 B D B A D D D C B A D A C A B A C C A B Q1 ( B) A 1s2 2s1 2p1 Excited state of Group 2 B 2s2 2p2 Ground state of Group 14 C 2s1 2p3 Excited state of Group 14 D 3p4 Excited state Q2 ( B) σ bonds formed by head-on overlap of either s or p orbitals. π bonds formed by side-to-side overlap of p-orbitals. s-or bitals are spherical and thus cannot overlap in a way to form π bonds. Q3 (C) Q4 (C) Calcium and sodium are metals. Their melting points depend on the strength of their metallic bonds. Strength of metallic bonds depend on: • charge of metal ion • size of metal ion • no. of valence electrons which can be delocalised (more delocalised electrons ⇒ greater attraction between metal cations and delocalised electrons) A true, but irrelevant B true, but irrelevant C Ca2+ has a higher charge and hence higher charge density than Na+. D true, but irrelevant. This option discusses the total no. of electrons in each cation and not th