Science (English Medium) कक्षा १२ - CBSE Question Bank Solutions

Concentrated nitric acid, upon long standing, turns yellow brown due to the formation of ____________.

Ethyl alcohol can be prepared from Grignard reagent by the reaction of ____________.

Alkenes convert into alcohols by ____________.

Which of the following reacts with NaOH to give alcohol?

Commercially carboxylic acids are reduced to alcohols by converting them to the ______.

Which of the following statements is incorrect regarding glucose?

The symbols D and L represents ____________.

Which one of the following compounds is different from the rest?

When glucose reacts with bromine water, the main product is ____________.

Glucose does not react with ____________.

Glucose reacts with acetic anhydride to form ______.

Which of the following properties of glucose cannot be explained by its open chain structure?

(i) Glucose does not form hydrogen sulphite with NaHSO₃.

(ii) On oxidation with HNO₃ glucose gives saccharic acid.

(iii) Glucose is found to exist in two different crystalline forms which are named as α and β.

Glucose is found to exist in two different α and β crystalline forms. These forms can be obtained by:

(i) The α form of glucose is obtained by crystallisation from a concentrated solution of glucose at 303 K.

(ii) The β form of glucose is obtained by crystallisation from a concentrated solution of glucose at 303 K.

(iii) The β form is obtained by crystallisation from hot and saturated aqueous solution at 371 K.

(iv) The α form is obtained by crystallisation from hot and saturated aqueous solution at 371 K.

Reduction of glucose by HI suggest that ____________.

The reaction of glucose with red P + HI is called ____________.

Which of the following reactions of glucose can be explained only by its cyclic structure?

Which is the least stable form of glucose?

A solution of D-glucose in water rotates the plane polarised light ____________.

The number of chiral carbon atoms present in cyclic structure α-D(+) glucose:

The α-D glucose and β-D glucose differ from each other due to difference in carbon atom with respect to its ____________.