: Understand trends in Group 2 and Group 17, particularly reactivity with water and oxygen. Common pitfalls include misidentifying the electronic configuration of transition metal ions (e.g., X2+cap X raised to the 2 plus power having 5 unpaired electrons). Study Resources

Carelessness in maintaining the correct number of significant figures in final numerical answers. Phase Diagrams: Failing to compare water and cap N a cap C l solution on a diagram; instead, sketching two separate graphs.

: Detailed step-by-step solutions for 2020 Semester 2 are available on Scribd and Course Hero .

cannot coordinate more than 4 water molecules due to a lack of empty d-orbitals.

This article provides a breakdown of the , focusing on marking schemes, common pitfalls, and study strategies for these high-weightage topics. 2020 STPM Chemistry Semester 2 Paper Overview