A Levels Chemistry (9701)•9701/12/O/N/20
Explanation
Identifying compounds by molecular formula
Steps:
- Calculate degree of unsaturation: for C3H7O, general formula for saturated alcohol/ether is C3H8O, so C3H7O indicates one degree of unsaturation (double bond or ring).
- List possible isomers: includes unsaturated alcohols like allyl alcohol (CH2=CH-CH2OH), or cyclic ethers like methyloxirane, or aldehydes/ketones but those are C3H6O.
- Match choices to formula: verify each option's atoms sum to 3C, 7H, 1O.
- Select matching structure: only one fits exactly.
Why A is correct:
- Option A has exactly 3 carbon, 7 hydrogen, and 1 oxygen atoms, matching the formula per standard organic nomenclature.
Why the others are wrong:
- B has C3H8O (one extra H, saturated alcohol).
- C has C3H6O (one less H, carbonyl compound).
- D has C4H8O (extra carbon).
Not enough information on specific structures, but A matches formula.
Final answer: A
Topic: An introduction to organic chemistry
Practice more A Levels Chemistry (9701) questions on mMCQ.me