Write the reactions involved when D-glucose is treated with the following reagents: (a) HCN (b) Br\(_2\) water
Write the reactions involved when D-glucose is treated with the following reagents: (a) HCN (b) Br\(_2\) water
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Solution and Explanation
Reactions of D-Glucose
(a) Reaction of D-glucose with HCN
When D-glucose is treated with hydrogen cyanide (HCN), it undergoes cyanohydrin formation. The reaction occurs at the aldehyde group, resulting in the formation of D-glucose cyanohydrin.
\[ \text{D-glucose} + HCN \rightarrow \text{D-glucose cyanohydrin} \]
(b) Reaction of D-glucose with Br\(_2\) water
When D-glucose is treated with bromine water (a mild oxidizing agent), it specifically oxidizes the aldehyde group at C-1 to a carboxylic acid, producing gluconic acid.
\[ \text{D-glucose} + Br_2\text{(water)} \rightarrow \text{Gluconic acid} \]
These reactions demonstrate the aldehydic nature of glucose and its ability to undergo addition and oxidation reactions.
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\includegraphics[width=1\linewidth]{chi25.png} - A solution containing 15 g urea (molar mass = 60 g mol\(^{-1}\)) per litre of solution in water has the same osmotic pressure (isotonic) as a solution of glucose (molar mass = 180 g mol\(^{-1}\)) in water. Calculate the mass of glucose present in one litre of its solution.
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