Practical Organic Chemistry — Page 2 | JEE Chemistry

Q11

Which of the following is a bactericidal antibiotic ?

A Erythromycin

B Tetracycline

C Chloramphenicol

D Ofloxacin

Correct Answer

Option D

Solution

Bactericidal antibiotics are those that can kill bacteria mainly by inhibiting cell wall synthesis, while bacteriostatic antibiotics are those that inhibit the growth of bacteria by interfering with their growth and metabolism.

Tetracycline, chloramphenicol and erythromycin are bacteriostatic antibiotics, while ofloxacin is bactericidal antibiotic.

Q12

Which one of the following types of drugs reduces fever?

A Analgesic

B Antipyretic

C Antibiotic

D Tranquiliser

Correct Answer

Option B

Solution

An antipyretic is a drug which is responsible for lowering the temperature of the feverish organism to normal but has no effect on normal temperature states.

Q13

Aspirin is known as :

A Acetyl salicylic acid

B Phenyl salicylate

C Acetyl salicylate

D Methyl salicylic acid

Correct Answer

Option A

Solution

Aspirin is acetyl derivative of salicylic acid.

Q14

Which of the following compounds is not an antacid?

A Cimetidine

B Ranitidine

C Phenelzine

D Aluminium hydroxide

Correct Answer

Option C

Solution

Phenelzine is an antidepressant, while others are antacids.

Q15

Which of the following is an anionic detergent ?

A Sodium stearate

B Sodium lauryl sulphate

C Cetyltrimethyl ammonium bromide

D Glyceryl oleate

Correct Answer

Option B

Solution

Sodium lauryl sulphate

\left( {{C_{11}}{H_{23}}C{H_2}OSO_3^ - N{a^ + }} \right)

is an anionic detergent. Glycery oleate is a glyceryl ester of oleic acid. Sodium stearate

\left( {{C_{17}}{H_{35}}CO{O^ - }N{a^ + }} \right)

is a soap. Cetyltrimethyl ammonium bromide

\left[ {C{H_3}{{\left( {C{H_2}} \right)}_{15}}\,\mathop N\limits^ + {{\left( {C{H_3}} \right)}_3}} \right]B{r^ - }

is a cationic detergent.

Q16

The reason for “drug induced poisoning” is :

A Binding reversibly at the active site of the enzyme

B Bringing conformational change in the binding site of enzyme

C Binding irreversibly to the active site of the enzyme

D Binding at the allosteric sites of the enzyme

Correct Answer

Option C

Solution

Some drugs acts as allosteric effectors.

They can cause large changes in enzymatic activity by binding with a site other than the active site.

This other site is also called an allosteric site.

When it causes a decrease in enzyme activity, the effector molecules are called allosteric inhibitors.

Q17

The mixture of chloroxylenol and terpineol is an example of

A antiseptic

B pesticide

C disinfectant

D narcotic analgesic

Correct Answer

Option A

Solution

The mixture of chloroxylenol and terpineol is known as Dettol. It acts as an Antiseptic.

Q18

Which amongst the following is not a pesticide?

A DDT

B Organophosphates

C Dieldrin

D Sodium arsenite

Correct Answer

Option D

Solution

NaAsO2 (Sodium arsenite) is an insecticide, antibacterial agent herbicide.

Q19

A chemical which stimulates the secretion of pepsin is :

A Anti histamine

B Cimetidine

C Histamine

D Zantac

Correct Answer

Option C

Solution

Histamine stimulates the secretion of pepsin and hydrochloric acid in the stomach.

Q20

An antiseptic dettol is a mixture of two compounds 'A' and 'B' where A has 6

\pi

electrons and B has 2

\pi

electrons. What is 'B'?

A Bithionol

B Terpineol

C Chloroxylenol

D Chloramphenicol

Correct Answer

Option B

Solution

Dettol is a mixture of chloroxylenol and terpineol.

Chloroxylenol has $6 \pi$ electrons and terpineol has $2 \pi$ electrons.

Hence B is terpineol.