In the Fischer esterification reaction a carboxylic acid reacts with an excess of alcohol in acidic conditions to form an ester. During the reaction the sp2 hybridized carbonyl carbon of the acid forms an sp3 hybridized intermediate before returning to sp2 hybridization in the product. Draw the structure of the neutral sp3 hybridized intermediate and the ester product in the reaction between pentanioc acid and n-propanol. Which reactant provides the oxygen atom found in the ester linkage: Pentanoic acid, or propanol?

it is the most commonly accepted one

what are the statements

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.