How do you distinguish aldehyde from ketone?

Aldehydes give a positive Tollens’ test (silver mirror) and Fehling’s test (red precipitate), while ketones do not react — this is the standard way to tell them apart.

Why are aldehydes more reactive than ketones?

Aldehydes have less steric hindrance and less electron-donating alkyl groups around the carbonyl carbon, making it more open to nucleophilic attack than in ketones.

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Difference Between Aldehyde and Ketone

Aldehydes and ketones both contain the carbonyl group (C=O) but differ in its position and in their chemical reactivity.

In short

In aldehydes the carbonyl carbon is bonded to at least one hydrogen and sits at the end of the chain (–CHO); in ketones the carbonyl carbon is bonded to two carbon atoms and sits within the chain.

Aldehyde vs Ketone — Comparison Table

Basis	Aldehyde	Ketone
Carbonyl position	Terminal (end)	Within the chain
General formula	R–CHO	R–CO–R′
Groups on carbonyl C	At least one H	Two carbon (alkyl/aryl) groups
Tollens’ test	Positive (silver mirror)	Negative
Fehling’s test	Positive (red ppt)	Negative
Reactivity	More reactive	Less reactive

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Frequently Asked Questions — Aldehyde vs Ketone

How do you distinguish aldehyde from ketone?: Aldehydes give a positive Tollens’ test (silver mirror) and Fehling’s test (red precipitate), while ketones do not react — this is the standard way to tell them apart.
Why are aldehydes more reactive than ketones?: Aldehydes have less steric hindrance and less electron-donating alkyl groups around the carbonyl carbon, making it more open to nucleophilic attack than in ketones.

Difference Between Aldehyde and Ketone

Aldehyde vs Ketone — Comparison Table

Frequently Asked Questions — Aldehyde vs Ketone

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