EJC 2024 H2 Chemistry Planning Worked Examples and Practice Questions Booklet

W O R K E D E X A M P L E S A N D P R A C T I C E Q U E S T I O N S P a g e | 2 Contents 1 Volumetric Analysis ................................ ................................ ................................ ................. 4 1.1 Acid-Base Titrations ................................ ................................ ................................ ......... 5 Worked Example 1A: Direct Titration ................................ ................................ ......................... 5 Worked Example 1B: Back Titration ................................ ................................ ........................... 7 1.2 Redox Titrations ................................ ................................ ................................ ................ 9 Worked Example 1C: Redox Titration Involving MnO4 (MJC 2018/4/1e) ................................ ... 9 Practice Question 1A: Redox Titration Involving Autocatalytic Reaction (NYJC 2018/4/1g) ..... 12 Practice Question 1B: Redox Titration Involving I2 and S2O32− (JJC 2018/4/3) ......................... 13 2 Gravimetric Analysis ................................ ................................ ................................ ............. 15 Worked Example 2A: Volatilisation Gravimetry (9259 2008) ................................ .................... 16 Practice Question 2A: Volatilisation Gravimetry Involving CuSO4·nH2O ................................ ... 18 Practice Question 2B: Volatilisation Gravimetry Involving Carbonates (SAJC 2018/4/1g) ........ 18 Practice Question 2C: Precipitation Gravimetry (ACJC 2019/4/1g) ................................ .......... 19 3 Gas Collection Experiments................................ ................................ ................................ .. 20 Worked Example 3A (DHS 2018/4/2a) ................................ ................................ ..................... 21 Practice Question 3A (TJC 2018/4/1c) ................................ ................................ ..................... 24 4 Chemical Energetics ................................ ................................ ................................ .............. 25 4.1 Calorimetry ................................ ................................ ................................ ...................... 26 Worked Example 4A: Finding Enthalpy Change of Solution ................................ ..................... 28 Worked Example 4B: Finding Enthalpy Change of Combustion ................................ ............... 31 Practice Question 4A (CJC 2018/4/2) ................................ ................................ ...................... 34 Practice Question 4B (HCI 2018/4/3) ................................ ................................ ....................... 34 4.2 Thermometric Titrations ................................ ................................ ................................ . 36 Worked Example 4C (CJC 2019/4/3) .......