A-LevelChemistryEquilibriaOct/Nov 2013Paper 1 Q91 Mark
Nitrogen reacts with hydrogen to produce ammonia. N2(g) + 3H2(g) ⇌ 2NH3(g) A mixture of 2.00 mol of nitrogen, 6.00 mol of hydrogen, and 2.40 mol of ammonia is allowed to reach equilibrium in a sealed vessel of volume 1 dm³ under certain conditions. It was found that 2.32 mol of nitrogen were present in the equilibrium mixture. What is the value of Kc under these conditions?
A(1.76)² / (2.32)(6.96)³
B(1.76)² / (2.32)(6.32)³
C(2.08)² / (2.32)(6.32)³
D(2.40)² / (2.32)(6.00)³
✓ Correct Answer
The correct answer is A: (1.76)² / (2.32)(6.96)³
📋 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