Chemistry

This is a multiple choice answer as classified in NCERT Exemplar

(b) Artificial sweeteners are non-caloric substitutes for sugar. They are often intensely more sweet than sugar but do not enhance nutritional value of food. Vitamins and minerals are essential nutrients because they perform hundreds of roles in the body.

Amino acids will also enhance the nutritional value of food.

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: (C)

In the process of nitration of benzene, firstly H₂SO₄ dissociates into H⁺ and HSO₄−. The proton produced further reacts with HNO₃ to give a positively charged complex that is unstable and dissociates into nitronium ions and water as products. The nitronium ion is an electron-deficient species i.e. electrophile that attacks the electron cloud of the benzene ring.

H₂SO₄  (conc.) ? H⁺+HSO₄⁻

H⁺+HNO₃? H₂NO₃⁺

H₂NO₃⁺? NO₂⁺ + H2O

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: (B) 

Primary aliphatic amines react with nitrous acid to form aliphatic diazonium salts, which are unstable and release nitrogen gas and alcohol quantitatively.

This is a multiple choice answer as classified in NCERT Exemplar

(d) Sucralose is an artificial sweetening agent which is 600 times sweeter than sucrose and does not provide calories.

This is a multiple choice answer as classified in NCERT Exemplar

(c) Inhibitors are chemical substances which tend to reduce the activity of a particular enzyme. Generally, a weak bond such as H-bonding, van there Waals interaction, etc. is formed between the enzyme and the inhibitor.

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: (C)

Methyl amine reacts with HNO₃ form methanol with release of nitrogen gas and water as side products.

This is a multiple choice answer as classified in NCERT Exemplar

(c) Drugs usually interact with biomolecules such as carbohydrates, lipids, proteins and nucleic acids. These are called drug targets. Vitamins are not a target molecule for drug function in body.

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: (D) 

The greater the electron density towards the ring, the greater its basic strength.

The electron withdrawing group reduces basic strength, whereas the electron donating group increases basic strength.

This is a multiple choice answer as classified in NCERT Exemplar

(c) Polyethyleneglycols are used in the preparation of non-ionic detergents.

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: (B) 

Hoffmann invented a method for producing primary amines by treating an amide with bromine in an aqueous or ethanolic sodium hydroxide solution. An alkyl or aryl group migrates from the amide's carbonyl carbon to the nitrogen atom during this degradation reaction.