250+ TOP MCQs on Inorganic Chemical – Urea

Chemical Industry Multiple Choice Questions on “Inorganic Chemical – Urea”.

1. What is the molecular weight of Urea?
a) 60
b) 70
c) 80
d) 90

Answer: a
Clarification: Molecular formula of Urea is NH₂CONH₂. Weight of nitrogen, oxygen, carbon and hydrogen is 14, 16, 12 and 1 respectively. Therefore, Weight of Urea = 14*2+4+12+16 = 60.

2. For which of the mentioned does Urea serve the purpose?
a) Fertilizer
b) Formaldehyde resins
c) Melamine
d) All of the mentioned

Answer: d
Clarification: Urea is used as solid fertilizer (53%), liquid fertilizer (31%) and other miscellaneous applications such as animal feed, formaldehyde resins, melamine and adhesives.

3. Urea-ammonium nitrate solution is regarded as which of the mentioned?
a) Nitrogen fertilizer
b) Phosphate fertilizer
c) Potassium fertilizer
d) Mixed fertilizer

Answer: a
Clarification: Urea-ammonium nitrate solution is most popular nitrogen fertilizer.

4. Which of the mentioned statements is true?
a) Melamine is synthesized by condensation of urea molecules
b) Melamine is synthesized by thermal cracking hydrocarbons
c) Melamine is synthesized by polymerization of urea molecules
d) None of the mentioned

Answer: a
Clarification: Melamine is synthesized by condensation of urea molecules.

5. Ammonium carbamate decomposition results in which of the mentioned?
a) Urea
b) DDT
c) Ammonium nitrate
d) Ammonium hydroxide

Answer: a
Clarification: Ammonium carbamate decomposition is one of the methods of producing urea.

6. What kind of reaction takes place when compressed ammonia and CO₂ are reacted?
a) Highly Endothermic
b) Exothermic
c) Endothermic
d) None of the mentioned

Answer: b
Clarification: When ammonia and CO₂ are compressed separately and reacted, reaction is a exothermic in nature with ΔΗ^o = -37.4 Kcal.

7. Into which of the mentioned equipment are compressed NH₃ and CO₂ added for production of urea by Ammonia carbamate decomposition?
a) CSTR
b) Parr Reactor
c) Autoclave
d) Plug type reactor

Answer: c
Clarification: Ammonia and CO₂ are compressed separately and added to a high-pressure autoclave, which is water -cooled.

8. What is the average residence time of the autoclave on continuous basis when fed with compressed ammonia and CO₂?
a) 1-2 hours
b) 1.5-2 hours
c) 1.5-2.5 hours
d) 1.5-3 hours

Answer: b
Clarification: The average residence time in the autoclave, which is operated on continuous basis, is 1.5-2 hours.

9. What are the resultant compounds after reaction of compressed NH₃ and CO₂ in autoclave on continuous basis?
a) Urea
b) Ammonium Carbamate
c) H₂O
d) All of the mentioned

Answer: d
Clarification: A mixture of urea, ammonium carbamate, H₂O and unreacted NH₃+CO₂ results after reaction between compressed CO₂ and NH₃ in an autoclave.

10. In which of the mentioned equipment does further decomposition of carbamate take place?
a) Atmospheric flash drum
b) Flash evaporator
c) Distillation tower
d) Cooling tower

Answer: a
Clarification: The aqueous solution of carbamate and urea is passed to the atmospheric flash drum for further decomposition of carbamate.