2025 · Paper 2 · Chemistry
Question 13
The printed question, the official key, and each model’s JSON answer plus the reasoning it wrote.
ChemistryPaper 2Numerical
Q13
Official 2.4 – 2.55
Model answers
Claude Fable 5.1
Anthropic
Correct4 / 4
2.49
Claude Fable 5.1 reasoning
Osmotic pressure: π = hρg = (0.02 m)(1000 kg m⁻³)(10 m s⁻²) = 200 Pa π = (c/M)RT, where c = 2.00 g dm⁻³ = 2.00 kg m⁻³ M = cRT/π = (2.00 × 8.3 × 300)/200 = 4980/200 = 24.9 kg mol⁻¹ = 24900 g mol⁻¹ = 2.49 × 10⁴ g mol⁻¹ So X = 2.49
GPT 6 Astra
OpenAI
Correct4 / 4
2.49
GPT 6 Astra reasoning
No written reasoning was returned for this item.
GPT 5.6 Luna
OpenAI
Correct4 / 4
2.49
GPT 5.6 Luna reasoning
No written reasoning was returned for this item.