Class 12th

This is a short answer type question as classified in NCERT Exemplar

A person suffers from depression when he has low levels of noradrenaline. Noradrenaline is a neurotransmitter which plays a role in mood changes. Low level of noradrenaline lowers the signal-sending activity and make the person suffer from depression.

This is a short answer type question as classified in NCERT Exemplar

Analgesics are neurologically active pain killing drugs that reduce pain without causing impairment of consciousness, mental confusion, co¬ordination or paralysis or some other disturbances of nervous system. For example, aspirin, ibuprofen, paracetamol, diclofenac sodium, etc.

This is a short answer type question as classified in NCERT Exemplar

Soaps are biodegradable. The detergents are quite stable and are non- biodegradable because of branching in hydrocarbon chain hence cause water pollution. Therefore, it is safer to use soap from the environmental point of view.

This is a short answer type question as classified in NCERT Exemplar

Straight chain hydrocarbons in synthetic detergent leads to easy biodegrad-ability because the branched chain hydrocarbon tail is a source of pollution. Therefore, lesser the branching more is the biodegradability.

This is a short answer type question as classified in NCERT Exemplar

Micelle formation of the detergent can be shown as:

This is a short answer type question as classified in NCERT Exemplar

Non-ionic detergents such as polyethylene glycol stearate are used as dishwashing soaps.

This is a short answer type question as classified in NCERT Exemplar

Cationic detergents such as cetyltrimethyl ammonium bromide are used in hair shampoos and hair conditioners.

This is a short answer type question as classified in NCERT Exemplar

Anionic detergents such as cetyltrimethyl ammonium bromide are used in hair shampoos and hair conditioners.

This is a short answer type question as classified in NCERT Exemplar

Detergents (which are not biodegradable) persist in water even after sewage treatment and that causes foaming in river water.

This is a short answer type question as classified in NCERT Exemplar

Acid-base titration can be used to determine the excess amount of alkali in soap. The excess alkali left after hydrolysis of oils or fats can be the source of alkalinity in soap.