250+ TOP MCQs on Organic Chemicals and Answers

Chemical Technology Multiple Choice Questions on “Organic Chemicals”.

1. Which of the mentioned are the principal constituents of an organic compound?
a) Carbon, Oxygen and Nitrogen
b) Carbon, Oxygen and Hydrogen
c) Carbon, Oxygen and Sulphur
d) Carbon, Oxygen and Sulphur

Answer: b
Clarification: Any compound containing Carbon, Hydrogen and Oxygen as principal constituents is an organic compound.

2. Identify the organic chemical from the mentioned?
a) Benzene
b) Silicates
c) Aluminates
d) Sulphur

Answer: a
Clarification: Benzene’s chemical formula is C₆H₆, which help us, identify it as organic chemical whereas the rest are inorganic, as they don’t posses Carbon, Oxygen, Hydrogen as chief constituents.

3. Which of the mentioned names is apt for Acetic Acid?
a) Methanoic Acid
b) Ethanoic Acid
c) Butanoic Acid
d) Pentanoic Acid

Answer: b
Clarification: Acetic acid’s formula is CH₃COOH, which consists of acetyl group (Ethanoyl group), So Acetic Acid can also be called as ethanoic acid (presence of 2 carbons).

4. Which of the mentioned can also be a formula of acetic acid?
a) C₂H₄O₂
b) C₂H₄O₃
c) CH₄O₂
d) C₃H₄O

Answer: a
Clarification: Acetic acid’s formula is CH₃COOH, summing up all Carbons, Hydrogen and Oxygen will result in C₂H₄O₂.

5. What is the capacity of the refinery by Reliance Industry? Where is it located?
a) 10 million ton, Assam
b) 15 million ton, Jamnagar
c) 10 million ton, Ahmedabad
d) 15 million ton, Gandhinagar

Answer: b
Clarification: Reliance Industry started one of the largest refineries in Jamnagar whose capacity is 15 million ton.

6. Natural Gas largely constitutes of which of the mentioned?
a) Ethane
b) Methane
c) Butane
d) Pentane

Answer: b
Clarification: Methane is one of the major constituents of Natural Gas (about 75%).

7. Which of the mentioned is the simplest method of producing ethylene on large scale?
a) Thermal cracking of ethane
b) Deoxidation of ethylene oxide
c) Dehydration of ethanol
d) Dehalogenation of Ethyl Chloride

Answer: a
Clarification: Steam/Thermal cracking if ethane is the easiest and economical means to produce ethylene on large scale, the rest of the reactions are not feasible due to low conversion, However, on laboratory scale ‘c’ can be achieved.

8. Molecular weight of perchloroethylene is approximately? (Cl-35.5, C-12)
a) 165
b) 166
c) 167
d) 168

Answer: b
Clarification: Perchloroethane’s formula is C₂Cl₄. Therefore, its weight will be 12*2+35.5*4 = 166.

9. Pyrolsis of CCl₄ will result in which of the mentioned compound?
a) Perchloroethylene
b) Trichloroethylene
c) Dichloroethylene
d) Hypochlorous acid

Answer: a
Clarification: Pyrolysis is breaking down of molecules, when two moles of percholoroethylene is taken and pyrolysis is done, it yields perchloroethane and chlorine.

10. Which of the mentioned catalyst is used in preparation of synthetic ethanol?
(Process is hydration of ethylene)
a) Zirconium
b) Platinum
c) Phosphoric acid on celite
d) Phosphoric acid on silica

Answer: c
Clarification: Synthetic ethanol is made by dehydration of ethylene using phosphoric acid on celite catalyst.