RI H2 Chemistry TYS Solutions 2013-2019

© Raffles Institution Changes to 2013 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 28 Not in syllabus 30 Not in syllabus 34 Amend question “In the reaction below, M represents a Group 2 element.” 37 Option 3 is not in syllabus Paper 2 4(a)(i) Not in syllabus. 4(d)(i) Not in syllabus. Ca(NO3)2(s)  CaO(s) + 2NO2(g) + 1 2 O2(g) 5(a), (c) and (d) - Not in syllabus. Can do 5b, 5e and 5f Paper 3 3a: Change P4O6 to P4O10 4(e)(ii) Bond energy of C=O in CO2 in the Data Booklet (for new syllabus) is the same as that given by the question

© Raffles Institution Q1 3H3PO4  H5P3O10 + 2H2O Ans : B Q2 No. of protons No. of neutrons No. of electrons (A) D3O+ 11 11 10 (B) H3O+ 11 8 10 (C) NH2 9 7 10 (D) OD 9 9 10 Ans: B Q3 Before gaining e After gaining e (A) C+: 1s22s22p1 C: 1s22s22p2 (B) N : 1s22s22p3 N : 1s22s22p4 (C) Si: 1s22s22p63s23p3 Si2: 1s22s22p63s23p4 (D) P+: 1s22s22p63s23p2 P: 1s22s22p63s23p3 Ans: D Q4 660; 1267; 2218; 3313; 7863; 9500 607 951 1095 4550 1637 Since the largest jump is between 4th and 5th ionisation energies, M is a Group 14 element. Ans: C Q5 Substances with giant covalent structure generally do not conduct electricity in all physical states since all its valence electrons are used up for covalent bonding. Ans: A Q6 The behaviour of a gas is most ideal at: (i) low pressure At low pressure, the gas particles are far apart from one another . Hence the volume occupied by gas particles is negligible compared to the volume of the container and the intermolecular forces of attraction are negligible as the gas particles are far apart. (ii) high temperature At high temperature, the gas particles have higher kinetic energy so that the intermolecular forces of attraction between them are negligible. Ans: C Q7 Hrxn = mHfo (pdts)  nHfo (rxts) Hrxn = Hfo (CH3CO2Na.3H2O(s))  3Hfo (H2O(l))  Hfo (CH3CO2Na(aq)) Ans: A Q8 Since a reaction occurs vigorously, G < 0 Reaction is endothermic (H > 0)  temp decreases. G= H  TS  TS is neg