Alcohols have much higher boiling points than alkanes of similar molar mass because
Correct answer: A. their molecules are hydrogen bonded to one another
- A. their molecules are hydrogen bonded to one another
- B. they are ionic compounds
- C. their covalent bonds are stronger
- D. they have larger molecules
Explanation
The hydroxyl group allows hydrogen bonding between molecules, and a great deal of extra energy is needed to break those bonds before the liquid can boil, so ethanol boils at 78 degrees Celsius while propane, of similar mass, boils at minus 42. The same hydrogen bonding makes the shorter alcohols completely miscible with water. Boiling point does not depend on the strength of bonds inside the molecule.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? support@testustad.com
About Alcohols
Alcohols contain a hydroxyl group attached to a saturated carbon atom and are classified as primary, secondary or tertiary. Their nomenclature, hydrogen bonding, acidity, oxidation, dehydration, reaction with sodium and conversion to haloalkanes are covered, along with the distinction between alcohols and phenols, where the hydroxyl group is attached directly to an aromatic ring.
Practise Alcohols and Phenols
535 free Alcohols and Phenols MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Alcohols questions
Oxidation of a primary alcohol with acidified potassium dichromate, distilling the product as it forms, gives
A tertiary alcohol is not readily oxidised because the carbon carrying the hydroxyl group
Dehydration of ethanol with concentrated sulphuric acid at about 170 degrees Celsius gives
Ethanol reacts with sodium metal to give