A-LevelChemistryNitrogen and sulfurMay/June 2011Paper 1 Q361 Mark
In a car engine pollutant oxide Y, which contains non-metallic element X, is formed. Further oxidation of Y to Z occurs in the atmosphere. In this further oxidation, 1 mol of Y reacts with 0.5 mol of gaseous oxygen. X could be either nitrogen or sulfur. Which statements about X, Y and Z can be correct? 1 The oxidation number of X increases by two from Y to Z. 2 Y may have an unpaired electron in its molecule. 3 Y is a polar molecule.
A1, 2 and 3 are correct
B1 and 2 only are correct
C2 and 3 only are correct
D1 only is correct
✓ Correct Answer
The correct answer is A: 1, 2 and 3 are correct
📋 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