A-LevelChemistryElectrochemistryOct/Nov 2022Paper 4 Q311 Marks
Data should be selected from Table 3.1 in order to answer some parts of this question. Table 3.1 electrode reaction | E°/V Mg²⁺ + 2e⁻ ⇌ Mg | -2.38 Mn²⁺ + 2e⁻ ⇌ Mn | -1.18 Mn³⁺ + e⁻ ⇌ Mn²⁺ | +1.49 MnO₂ + 4H⁺ + 2e⁻ ⇌ Mn²⁺ + 2H₂O | +1.23 MnO₄⁻ + e⁻ ⇌ MnO₄²⁻ | +0.56 MnO₄⁻ + 4H⁺ + 3e⁻ ⇌ MnO₂ + 2H₂O | +1.67 MnO₄⁻ + 8H⁺ + 5e⁻ ⇌ Mn²⁺ + 4H₂O | +1.52
📋 Examiner Report & Trap Analysis
Common mistake: 62% of candidates selected the distractor because they confused... The examiner specifically designed this question to test whether students can differentiate between... To secure full marks, candidates must demonstrate...
🎯 Mark Scheme Breakdown
Award 1 mark for identifying the correct principle. Award 1 mark for showing clear working. Common errors include failing to convert units and misreading the scale. The examiner report notes that only 34% of candidates achieved full marks on this question.
🔒
Unlock the Examiner's Analysis
Sign up for free to reveal the full examiner report, trap analysis, and mark scheme breakdown for this question.
Sign Up Free to Unlock →Join thousands of Cambridge students already using Oracle Prep