250+ TOP MCQs on Alternative Fuels and Answers

Automotive Engine Auxiliary Systems Multiple Choice Questions on “ Alternative Fuels”.

1. Which are the two main alcohols used in the engine as a fuel?
a) Butanol and methanol
b) Propanol and butanol
c) Ethanol and propanol
d) Methanol and Ethanol
Answer: d
Clarification: Alcohols have been used as engine fuels for a long time, methanol and ethanol are the two main alcohols used in the engine as a fuel.

2. Which alcohol is used in racing car engine due to its high anti-knock rating?
a) Methanol
b) Ethanol
c) Propanol
d) Butanol
Answer: a
Clarification: Alcohols have a high anti-knock rating, due to which, especially methanol, have been used in racing car engines. Flame of methanol fire is difficult to be seen in daylight, due to which it may not be detected.

3. Flame of which alcohol is difficult to be seen in daylight?
a) Methanol
b) Ethanol
c) Propanol
d) Butanol
Answer: a
Clarification:Flame of methanol fire is difficult to be seen in daylight, like LPG, petrol or other fuels its flame doesn’t produce any color, due to which it may not be detected.

4. Due to which alcohol corrosion of rubber and aluminum parts occur?
a) Methanol
b) Ethanol
c) Propanol
d) Butanol
Answer: b
Clarification: Corrosion of rubber, magnesium, and aluminum parts occurs at higher ethanol percentages, and also it is electrically conducting, this can cause a problem with some electric fuel pumps.

5. Which alcohol is electrically conducting and used as fuel?
a) Methanol
b) Ethanol
c) Propanol
d) Butanol
Answer: b
Clarification: Ethanol is electrically conducting, many sensors and electrical devices are connected to the engine. This can cause a problem with some electric fuel pumps.

6. What is the reason for ethanol to be difficult to ignite at a lower temperature?
a) High combustion
b) Aroma
c) structure of hydrocarbon
d) Less volatile
Answer: d
Clarification: Pure ethanol is less volatile than petrol due to which it becomes difficult to ignite at lower temperatures, which means, starting a cold engine during winter is difficult.

7. Which Ethanol is not used in light-duty vehicles?
a) E95
b) E15
c) E10
d) E85
Answer: a
Clarification: E10, E15, and E85 are used for light-duty vehicles and E95 is used in Heavy-duty vehicles e.g., trucks and buses. Hence, E95 is the right answer.

8. The Natural Gas consists of 95% of which gas?
a) Methane
b) Butane
c) Propane
d) Ethane
Answer: a
Clarification: The natural gas, like petroleum, comes from underground reserves. It consists, mainly of 95% of methane and the remaining 5% comprises butane, propane, and ethane with a small amount of water vapor.

9. Compared to petrol, CNG combustion produces 25% less of what gas?
a) NOx
b) H
c) CO
d) CO₂
Answer: d
Clarification: Compared to petrol, compressed natural gas produces about 25% less CO₂ and due to high levels of methane, it gives the highest HC emission.

10. LNG consist of more than 98% of which gas?
a) Propane
b) Ethane
c) Methane
d) Butane
Answer: c
Clarification: During the liquefaction process, natural gas is cooled below its boiling point removing most of the water vapor, butane, propane, etc., so that LNG is more than 98% methane.

11. The LPG is a by-product of the fractional distillation of which fuel?
a) Coal
b) Kerosene
c) Diesel
d) Petrol
Answer: d
Clarification: The liquefied petroleum gas is a by-product of the fractional distillation of petrol, consisting mainly of Butane and propane, used as engine fuel.

12. Which are two Hydrocarbons present in LPG?
a) Butane and Pentane
b) Methane and ethane
c) Butane and propane
d) Pentane and Hexane
Answer: c
Clarification: The liquefied petroleum gas is a by-product of the fractional distillation of petrol, consisting mainly of Butane and propane, used as engine fuel.

13. Bio-diesel is made of what residuals?
a) Plant oil
b) Animal fat
c) Plant oil and animal fat
D) Edible oil
Answer: c
Clarification: Bio-diesel is an alternative to standard diesel fuel, and is made from biological sources instead of petroleum, it is made from plant oils or animal fat.