Which statements about reducing sugars are true? d‑glucose (an aldose) is a reducing sugar. the oxidation of a reducing sugar forms a carboxylic acid sugar. a disaccharide with its anomeric carbons joined by the glycosidic linkage cannot be a reducing sugar. reducing sugars contain ketone groups instead of aldehyde groups. a reducing sugar will not react with the cu2+ in benedict's reagent.

The true statements are given below.

Explanation:

1 D glucose is a reducing sugar

2 The oxidation of reducing sugar forms a carboxylic acid sugar.

D glucose is a reducing sugar because glucose contain a free hydroxyl group (-OH)in its anomeric carbon.

 The oxidation of reducing sugar result in the conversion of -CHO group in case of aldose sugar and -CH2OH group in case of ketose sugar into carboxylic acid(-COOH).

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.  

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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