Concept explainers
(a)
Interpretation: The number of stereogenic centers present in
Concept introduction: Carbohydrates are naturally occurring compounds. Carbohydrates are polyhydroxy
(b)
Interpretation: The hemiacetal carbon in
Concept introduction: Carbohydrates are naturally occurring compounds. Carbohydrates are polyhydroxy aldehydes and ketones. Galactose is a aldohexose as it contains six carbon atoms as well as an aldehyde functional group. The molecular formula of galactose
Aldehydes or ketones on reaction with one equivalent of alcohol form hemiacetal and on reaction with two equivalents of alcohol it forms acetals. This is nucleophilic addition reaction. These reactions takes place in presence of acids, commonly
Ethers contain only one alkoxy group on a carbon atom while acetals contain two alkoxy groups on a single carbon atom.
Hemiacetals contains one alkoxy group and one hydroxyl group attached to same carbon atom.
(c)
Interpretation: The structure of
Concept introduction: Carbohydrates are naturally occurring compounds. Carbohydrates are polyhydroxy aldehydes and ketones. Galactose is a aldohexose as it contains six carbon atoms as well as an aldehyde functional group. The molecular formula of galactose
(d)
Interpretation: The structure of poly hydroxy aldehyde that cyclizes to
Concept introduction: Carbohydrates are naturally occurring compounds. Carbohydrates are polyhydroxy aldehydes and ketones. Galactose is a aldohexose as it contains six carbon atoms as well as an aldehyde functional group. The molecular formula of galactose
Aldehydes or ketones on reaction with one equivalent of alcohol form hemiacetal and on reaction with two equivalents of alcohol it forms acetals. This is nucleophilic addition reaction. These reactions takes place in presence of acids, commonly
In
(e)
Interpretation: The products formed when
Concept introduction: Carbohydrates are naturally occurring compounds. Carbohydrates are polyhydroxy aldehydes and ketones. Galactose is a aldohexose as it contains six carbon atoms as well as an aldehyde functional group. The molecular formula of galactose
Aldehydes or ketones on reaction with one equivalent of alcohol form hemiacetal and on reaction with two equivalents of alcohol it forms acetals. This is nucleophilic addition reaction. These reactions takes place in presence of acids, commonly
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