All topicsHow many stable isomers of C₄H₈ are there?2025 national · question 5511%Which C–H bond has the smallest bond dissociation enthalpy?2019 national · question 5814%How many distinct acyclic compounds have the formula C₅H₁₀?2018 national · question 5718%
Organic and biochemistry
This is block 10 of 10, questions 55–60 on both the local section exam and national Part I. Across the 41 national questions where ACS published item statistics, qualifiers answered 38% correctly, which makes it the hardest of the 10 blocks.
What it covers
functional groupsnomenclatureisomerismstereochemistryreaction typespolymersbiomolecules
Where qualifiers lose points
% who got it rightThese are the organic and biochemistry questions the fewest national qualifiers answered correctly. If you can do these, the block is not your problem.
Every question is from a published past exam and carries its source. Practice adapts to what you miss, and anything you get wrong comes back on a spaced schedule. No account needed. See the other nine blocks.