Engineering Chemistry Multiple Choice Questions on “Petrochemicals”.
1. What does the word petrochemicals signify?
a) Chemicals based on coal
b) Chemicals based on rocks
c) Chemicals based on atmospheric conditions
d) Chemicals based on fertility
Answer: b
Clarification: The term “petrochemicals” means “chemicals based on rocks”. It refers to the chemicals and chemical products manufactured from raw materials derived from petroleum and its fraction as well as natural gas.
2. Which of the following raw material obtained from petroleum can be in preparation of acetic acid?
a) Acetone
b) Phosphoric acid
c) Ethylene
d) Tartaric acid
Answer: c
Clarification: On industrial level, ethylene is oxidised to form acetic acid. The reaction is as follows-
C2H4 + O2 → CH3COOH
Ethylene Oxygen Acetic acid
Acetic acid is used as a food preservative in the baking industry.
3. Which of the following is a non-petroleum source?
a) CaC2
b) H2S
c) Paraffin
d) Olefin
Answer: a
Clarification: Calcium carbide (CaC2) is a non-petroleum source that is not obtained from the fraction of petroleum or natural gas. Calcium carbide was earlier used for the production of acetylene, which was then recovered from fractions of petroleum.
4. Which of the following process is used to convert the mixture of saturated hydrocarbons obtained from petroleum into a more reactive material?
a) Hydrogenation
b) Acidification
c) Alkylation
d) Chlorination
Answer: d
Clarification: The petroleum feed stock obtained from the distillation has to be converted to more reactive starting material with the help of suitable conversion processes such as chlorination, controlled oxidation, cracking, catalytic reforming, catalytic dehydrogenation etc.
5. Which of the following product is obtained by controlled oxidation of liquefied petroleum gas (LPG)?
a) Fatty acids
b) Acetylene
c) Acetic acid
d) Sulphuric acid
Answer: c
Clarification: By the controlled oxidation of low boiling fraction and LPG, acetic acid and other acids are obtained. Fatty acids are obtained by controlled oxidation of straight chain paraffin’s and acetylene is obtained by thermal cracking of wide ranging hydrocarbons.
6. Petroleum proteins are obtained by __________________ of straight chain paraffin’s.
a) Fermentation
b) Controlled oxidation
c) Chlorination
d) Thermal cracking
Answer: a
Clarification: Petroleum proteins are obtained by the fermentation of straight chain paraffin’s. Single cell proteins are obtained by the fermentation of petroleum, in which microbes are used as fermenting agents.
7. Alpha olefins are obtained by the molecular separation of medium boiling hydrocarbons.
a) True
b) False
Answer: b
Clarification: Alpha olefins are obtained by catalytic dehydrogenation of straight chain paraffin’s. Straight chain hydrocarbons are obtained by molecular separation of medium boiling hydrocarbons.
8. By which of the following fractions of petroleum aromatic hydrocarbons are produced?
a) Low boiling fractions
b) Wide ranging hydrocarbons
c) Medium boiling hydrocarbons
d) Special closely boiling fractions
Answer: d
Clarification: By catalytic reforming and separation of special closely boiling fractions of petroleum, aromatic hydrocarbons are obtained, while by thermal cracking with steam of wide ranging hydrocarbons, olefins are produced.
9. Which of the following end product is produced by the ethylene obtained from petroleum?
a) Formaldehyde
b) Esters
c) Cellulose acetate
d) Synthetic rubber
Answer: c
Clarification: Ethylene is a primary raw material from which acetic acid is produced as secondary raw material and then cellulose acetate is obtained as the end product. Cellulose acetate is used in plastics, fibres etc.
10. Which of the following is a secondary raw material produced from propylene?
a) Acrylic acid
b) Isoprene
c) Vinyl acetate
d) Methanol
Answer: a
Clarification: Acrylic acid, acetone, butanol etc, are the secondary raw materials produced from propylene. The end product obtained from acrylic acid is ester which are used for the production of synthetic resins.
