Chemistry · General Awareness

Carbon and Fossil Fuels

1,756 Questions

Review fundamental concepts regarding carbon compounds, coal distillation, and fossil fuel formation. This segment covers the chemical properties and industrial applications of natural gas and crude oil. Practicing these questions will strengthen your chemistry foundation for general science sections.

Coal distillationPetroleum formationProperties of crude oilNatural gas applications

Carbon and Fossil Fuels Questions

Multiple choice

Which of the following is a component of jet fuel?

  1. Methylcyclopropane

  2. Methylcyclopentane

  3. Methylcyclohexane

  4. Methylcycloheptane
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Methylcyclohexane is a colourless liquid with a faint benzene-like odour. Its molecular formula is C7H14. Methylcyclohexane is used in organic synthesis and it is also used as a solvent for cellulose ethers. It is a component of jet fuel and correction fluids.

Multiple choice

Which of the following statements is correct?

  1. Mixed base type crude is generally rich in semi-solid waxes.
  2. Petroleum ether is used as solvent.
  3. In fractional distillation of petroleum, lower boiling fractions condense first.
  4. In fractional distillation of petroleum, diesel oil fraction is obtained between 180-250oC.

  1. Only 1

  2. Only 2

  3. Only 2 and 3

  4. Only 3

  5. Only 3 and 4
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This option is correct because in fractional distillation of petroleum, higher boiling fractions condense first; while the lower boiling fractions turn by turn.

Multiple choice

Which of the following statements is correct?

  1. Gasoline or petrol is obtained between 40-120oC during fractional distillation of crude oil.
  2. In fractional distillation of petroleum, higher boiling fractions condense first; while the lower boiling fractions turn by turn.
  3. Naphtha is used as solvent and in dry cleaning.

  1. Only 1

  2. Only 2

  3. Only 1 and 2

  4. Only 2 and 3

  5. Only 1, 2 and 3
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

This option is correct because in fractional distillation of petroleum, higher boiling fractions condense first; while the lower boiling fractions turn by turn so, petrol is obtained between 40-120 oC during fractional distillation of crude oil and solvent Naphtha is used as dry cleaner.

Multiple choice

Which of the following statements is/are correct? a. Crude oil is a non-renewable energy resource. b. Crude oil and natural gas are generally found in metamorphic rocks. c. The fraction of crude oil containing a mixture of hydrocarbons such as decane to hexadecane is called kerosene oil.

  1. Only a

  2. Only b

  3. Only a and c

  4. Only a and b

  5. Only b and c
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This option is correct because Crude oil is a non-renewable energy resource and found in sedimentary rocks and the fraction of crude oil containing a mixture of hydrocarbons, such as decane to hexadecane is called kerosene oil.

Multiple choice

Which of the following is incorrectly matched?

  1. Doctor’s process : industrial chemical process for removing sulfur compounds from sour gasoline
  2. Cottrell’s process : process of obtaining petroleum ether from crude oil
  3. Dubb’s process : advanced thermal cracking process

  1. Only 1

  2. Only 2

  3. Only 3

  4. Only 1 and 2

  5. Only 1, 2 and 3
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This option is wrong because Cottrell’s process is the process of freeing oil from water by allowing the crude to flow between two highly charged electrodes.

Multiple choice

Which of the following statements is not correct about the process of 'cracking' in the petrochemical industry?

  1. It requires high temperature.
  2. In catalytic cracking much lower pressure is required than thermal cracking.
  3. It converts small hydrocarbons to more useful bigger hydrocarbons.
  4. Petrol obtained from vapour phase cracking has better anti-knock properties than petrol from liquid phase cracking.

  1. Only 1

  2. Only 1 and 2

  3. Only 2 and 3

  4. Only 3

  5. Only 3 and 4
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This option is correct because Cracking is the decomposition of bigger hydrocarbon molecules into simpler, low boiling hydrocarbons of lower molecular weight.

Multiple choice

Reforming is a process used for

  1. making synthetic petrol.
  2. making low boiling hydrocarbons of lower molecular mass.
  3. improving antiknock characteristics of fuel.
  4. producing power alcohol.

  1. Only 1 and 2

  2. Only 2 and 3

  3. Only 3

  4. Only 3 and 4

  5. Only 4
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This option is correct because Reforming is a process of bringing about structural modifications in the component of straight-run gasoline for improving its antiknock properties.

Multiple choice

Consider the following crude fraction: uses combination ||| |---|---| |Crude fraction |Uses| |i. Naphtha|As solvent and in dry cleaning.| |ii. Asphalt|As fuel and lubricant.| |iii. Petroleum jelly|As lubricant and in cosmetics and medicines| |iv. Heavy oil|For getting gasoline by cracking process|

  1. Only i and iii

  2. Only i, ii and iii

  3. Only ii, iii and iv

  4. Only i, iii and iv

  5. Only i, ii and iv
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This option is correct because combinations i, iii and iv are correct. Combination ii is incorrect. Asphalt is used in water proofing of roofs and road making.

Multiple choice

Find the odd one out.

  1. Uranium

  2. Calcium

  3. Coal

  4. Petroleum

  5. Electricity
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Calcium is found in food.

Multiple choice

In which fuel, the government has decided to mix 'marker' for identifying adulteration?

  1. Kerosene

  2. Diesel

  3. Petrol

  4. All the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The government adds chemical markers to kerosene to identify adulteration in diesel, as kerosene is sometimes illegally mixed with diesel due to price differences. The marker helps detect this adulteration through testing. Diesel and petrol themselves do not require markers for this purpose.

Multiple choice

Which of the following best explains cracking in hydrocarbons?

  1. The decomposition of compound in the presence of air.

  2. The decomposition of compounds by heating in presence of air.

  3. The decomposition of alkanes by heating in absence of air.

  4. The decomposition of alkenes by heating in absence of air.

  5. The decomposition of compounds by heating in absence of air.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Yes, it is correct. The decomposition of compounds by heating in absence of air is called pyrolysis. Pyrolysis for alkanes is called cracking.