Class 12th

This is a Multiple Answer Type Questions as classified in NCERT Exemplar

(a) 5′ and 3′ linkages are present between pentose sugars of nucleotides.

Phosphodiester links the two nucleotides together to form a dinucleotide.

Between the pentose sugars of nucleotides, there are 5′ and 3′ connections. In the process of adding phosphate to a dinucleotide, a significant quantity of energy is consumed.

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans:  (A) 

The NH₂ group is directly attached to the benzene ring in aniline and other aryl amines. As a result, the unshared electron pair on the nitrogen atom is conjugated with the benzene ring, making it less available for protonation.

This is a multiple choice answer as classified in NCERT Exemplar

(d) All soaps are made by boiling fats or oils with suitable hydroxide. Variations are made by adding different raw materials. Sodium laurylsulphate and sodium dodecylbenzenesulphonate are anionic detergents.

This is a Multiple Answer Type Questions as classified in NCERT Exemplar

Ans: The Correct option is b.

Ascorbic acid is the chemical name for vitamin C. Aspartic acid is an amino acid, adipic acid is a dicarboxylic acid with an eight-carbon chain, and saccharic acid is a dicarboxylic acid made by oxidising glucose with HNO₃ Vitamin C is a water-soluble vitamin that serves a variety of activities in the human body.

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans:  (C)

Because of the electron-releasing nature of the alkyl group, it (R) pushes electrons towards nitrogen, making the unshared electron pair more available for sharing with the acid's proton. Furthermore, the +I effect of the alkyl group stabilizes the substituted ammonium ion formed from the amine by dispersing the positive charge.

As a result, alkylamines are more powerful bases than ammonia.

As a result, the basic nature of aliphatic amines should increase as the number of alkyl groups increases.

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: Correct answer: (D) 

This is a multiple choice answer as classified in NCERT Exemplar

(b) The compound that causes general antidepressant action on the central nervous system belongs to the class of tranquilizers.

This is a Multiple Answer Type Questions as classified in NCERT Exemplar

Ans: The Correct option is b.

The structure described in option (b) reflects sucrose, which has a C₁−C₂ glycosidic bond between α−D− glucose and β−D− fructose.

This is a non-reducing sugar since the reducing groups of glucose and fructose are involved in the creation of glycosidic linkages.

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: (B) Triethylamine 

The structure of the given amines are shown below.

This is a multiple choice answer as classified in NCERT Exemplar

(a) A narrow spectrum antibiotic is active against gram positive or gram negative bacteria.