A Level H2 Chemistry 2021 Paper 3 Answers -

Questions in this category targeted the group periodic trends, specifically looking at . Key Concept: Enthalpy of Solution ( ) Down Group 2

The final question focused on redox titrations and complex formation with Copper(II).

The reaction of an aldehyde or ketone with HCNcap H cap C cap N , catalyzed by trace NaCNcap N a cap C cap N NaOHcap N a cap O cap H Mechanism Steps: Generation of the CN−cap C cap N raised to the negative power nucleophile. Nucleophilic attack by CN−cap C cap N raised to the negative power A Level H2 Chemistry 2021 Paper 3 Answers

Amount of H+=50.01000×0.100×2=0.0100 molAmount of H raised to the positive power equals 50.0 over 1000 end-fraction cross 0.100 cross 2 equals 0.0100 mol (Note: Multiplying by 2 is mandatory because releases two protons per molecule).

Amount of F−=0.178 mol200 cm3×75.0 cm3=0.06675 molAmount of F raised to the negative power equals the fraction with numerator 0.178 mol and denominator 200 cm cubed end-fraction cross 75.0 cm cubed equals 0.06675 mol Questions in this category targeted the group periodic

Students were required to find the partial pressure of CO2cap C cap O sub 2

Geometry of complex ions and ligand exchange mechanisms. Nucleophilic attack by CN−cap C cap N raised

Qc = [HI]^2 / ([H2] [I2]) Qc = (0.50)^2 / (0.10 * 0.10) = 25

By isolating the variable for the y-axis, we rewrite the ideal gas equation:

The paper tested anomalies in Period 3 trends—specifically First Ionization Energy (IE)—and the properties of Group 17 halogens.

Gives you a choice between 2 questions, valued at 15 marks each.