Molecular-structure exam problem clinic
≈ 48 minMolecular-structure exam problem clinic
Exam questions often combine structure, shape, polarity and property in one sequence. Slow down and translate each command word. For a molecule, draw or infer a Lewis structure; count electron domains; name the molecular shape; decide whether bond dipoles cancel; then select intermolecular forces. A full explanation uses cause and consequence: 'Water is bent, so its polar O-H bond dipoles do not cancel; therefore the molecule is polar and can form hydrogen bonds.' Listing disconnected facts may earn fewer marks than a linked chain.
Work it through
For CO₂, draw O=C=O. Carbon has two domains, so the molecule is linear. The C=O bonds are polar, but their dipoles are equal and opposite in the linear geometry, so CO₂ is non-polar overall. Its intermolecular forces are London dispersion forces. This is a different conclusion from water even though both contain oxygen.
Mastery target
Answer a linked structure-and-property question with a visible reasoning chain from formula to shape to polarity to intermolecular force.
Why is CO₂ non-polar even though each C=O bond is polar?
Name the key chemistry term from Molecular-structure exam problem clinic that best fits the explanation and visual model.
Which chain best explains water's relatively high boiling point?
Which statement corrects a common misunderstanding in Molecular-structure exam problem clinic?