Read the parent chain, carboxyl group and stereochemical descriptor carefully, then draw or name the acid without losing branches, hydroxy groups or E/Z geometry.
This question concerns six isomers each with the molecular formula C5H10O2.
State which one of the isomers A, E and F has the highest boiling temperature. Justify your answer. (3)
An explanation that makes reference to the following points: - Isomer A (has the highest boiling temperature) (1) - (Isomer A has the) only molecules held together by hydrogen bonding / Isomer A forms hydrogen bonds but E and F do not (1) - Hydrogen bonds are the strongest intermolecular forces (1) In general ignore reference to other intermolecular forces (but see below) Allow it forms hydrogen bonds Ignore it forms hydrogen bonds with other compounds/substances Ignore comments about straight chain so stronger London forces Allow hydrogen bonding is stronger than London forces and/or permanent dipoles Allow just 'forms strong hydrogen bonds’ (3)