2026 · Paper 1 · Chemistry
Question 3
The printed question, the official key, and each model’s JSON answer plus the reasoning it wrote.
ChemistryPaper 1Single correct
Q03
Official A
Model answers
Claude Fable 5.1
Anthropic
Correct3 / 3
A
Claude Fable 5.1 reasoning
BF3 (trigonal planar) and NH4+ (tetrahedral) are both symmetric with zero dipole moment. NF3 has a smaller dipole moment than NH3 because the N–F bond dipoles oppose the lone pair contribution, whereas in NH3 they reinforce it. Order: BF3 = NH4+ < NF3 < NH3
GPT 6 Astra
OpenAI
Correct3 / 3
A
GPT 6 Astra reasoning
No written reasoning was returned for this item.
GPT 5.5
OpenAI
Correct3 / 3
A
GPT 5.5 reasoning
No written reasoning was returned for this item.
Claude Sonnet 5
Anthropic
Correct3 / 3
A
Claude Sonnet 5 reasoning
No written reasoning was returned for this item.