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 chemistry energy rocks and minerals petroleum and natural gas fossil fuels

Crude oil is converted in to useful products by:

  1. drilling

  2. Solvay process

  3. roasting

  4. refining
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Crude oil in the raw form is obtained by drilling from the earth's crust. It has to be refined in order to convert it to useful products such as petrol, kerosene, diesel etc. The industrial plant where the refining of crude oil is done is called  an oil refinery. 

Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

Which of the following is not an important refinery process for upgrading the quality of lubrication oil?

  1. solvent refining

  2. deoiling

  3. clay treatment

  4. hydrotreatment
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In the refinery for lubricating oil, solvent refining, clay treatment and hydrotreatment are the important processes. The solvent used for refining purpose has to be pure. Clay treatment is done to remove colour, odour and sulphur from the oil. 

Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

When earth's crust is drilled, hydrocarbon came out first is:

  1. petroleum

  2. methane

  3. ethane

  4. butane
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Hydrocarbon is a compound containing carbon atoms and hydrogen atoms. Methane is the hydrocarbon found in the earth's crust. It is the simplest hydrocarbon. It is mainly used as fuel.

Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

Major source of propylene in a refinery is:

  1. visbreaking

  2. iso cracking process

  3. fluidised bed catalytic cracking

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

Propylene is often referred to as the crown prince of petrochemicals. Propylene is a byproduct of steam crackers and the varying amount of olefins is produced from steam crackers depending on the type of feedstock. Other sources of propylene may be the recovery of propylene from FCC light ends, Propane dehydrogenation and fluidized bed catalytic cracking.

Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

Which of the following is true from given statements?

  1. use of steam reduces the selectivity towards higher olefin production

  2. increase tube diameter increases the yield of propylene

  3. use of steam increases the selectivity towards higher olefin production

  4. increase tube diameter increases the yield of ethyne
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Use of steam increases the selectively towards higher olefin production.
The two most common petrochemical classes are olefins (including ethylene and propylene) and aromatics (including benzene, toluene and xylene isomers). Oil refineries produce olefins and aromatics by fluid catalytic cracking of petroleum fractions. Chemical plants produce olefins by steam cracking of natural gas liquids like ethane and propane. Aromatics are produced by catalytic reforming of naphtha. Olefins and aromatics are the building blocks for a wide range of materials such as solvents, detergents, and adhesives. Olefins are the basis for polymers and oligomers used in plastics, resins, fibres, elastomers, lubricants, and gels.
Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

Which of the following statements is true if fuel has high aniline point?

  1. Fuel has low paraffin

  2. Fuel has high diesel index

  3. Fuel has high aromatics

  4. Fuel has low diesel index
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Aniline point is the lowest temperature at which equal volumes of fresh aniline and an oil are completely miscible. Higher the aniline point, higher is the diesel index. Diesel index indicates the ignition quality of the fuel. 

Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

Steam consumption in steam cracker plant is high in case of:

  1. gas oil

  2. propane

  3. napthalene

  4. ethane
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In petroleum chemistry, Steam cracker plant is a process by which complex organic molecules are broken down to the simpler molecules using steam. Here, the cracking is done by using steam. Ethane cracking consumes the maximum amount of steam.

Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

A fuel with a higher octane rating:

  1. is less prone to auto-ignition

  2. can withstand a greater rise in temperature during the compression stroke

  3. has lower cetane number

  4. has lesser knocking
Reveal answer Fill a bubble to check yourself
A,B,C,D Correct answer
Explanation
  • The fuels with higher octane ratings will require high activation energies and are less prone to auto-ignition.
  • They can withstand the greater rise in temperature during the compression stroke of an internal combustion engine without auto igniting and thus allow more power to be extracted.
  • They have lower cetane number. Cetane number and octane rating are opposite to each other.
  • A fuel with higher octane rating leads to less engine knocking.
Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

Which is the most common type of octane rating worldwide?

  1. MON

  2. RON

  3. AKI

  4. Aviation gasoline octane rating
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Octane number can be determined by RON, MON and AKI.The most common method used for the measurement is RON. 

RON is determined by running the fuel in a test engine and comparing the results with those for mixtures of isooctane and $n$- heptane. 

Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

The fresh catalyst in catalytic reforming of petroleum is _______ prior to use.

  1. amalgamated

  2. brominated

  3. chlorinated

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

In catalytic reforming process; high octane number reformate is formed which is the main component of the motor, fuel, aviation gasoline or aromatic rich feedstock. The noble metals platinum and rhenium are the catalysts used on a silica or silica-alumina support base. Fresh catalyst is chlorinated prior to use.

Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

Hydrogenolysis reaction produces:

  1. heavy hydrocarbons

  2. light hydrocarbons

  3. only methane

  4. only butane
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Hydrogenolysis is a reaction where hydrogen is added to a compound and breaks that compound’s bonds, forming two molecules. This results in the formation of lighter hydrocarbons.

Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

Reformates are:

  1. high octane liquids

  2. low octane liquids

  3. mixture of high octane and low octane liquids

  4. none
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Catalytic reforming is a chemical process that is used to convert petroleum refinery naphthas, typically those which are having lower octane ratings into high octane liquid products which are termed as reformates. They are the components of high octane gasoline.

Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

The hydrocarbons present in diesel are from:

  1. $C _{15}\ to\ C _{18}$
  2. $C _{25}\ to\ C _{38}$
  3. $C _{35}\ to\ C _{58}$
  4. $C _{55}\ to\ C _{68}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Hydrocarbons present in

Gasoline $\Rightarrow C _3-C _{12}$
Napthalene $\Rightarrow C _8-C _{12}$
Kerosene/Jet fuels $\Rightarrow C _{11}-C _{14}$
Diesel & fuel oils $\Rightarrow C _{15}-C _{18}$
The hydrocarbons present in diesel are $C _{15}-C _{18}$.

Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

The petrol, octance number of which is $80$, has:

  1. $20\%$ n - heptane + $80\%$ iso-octane
  2. $20\%$ n - heptane + $80\%$ n-octane
  3. $80\%$ n - heptane + $20\%$ iso-octane
  4. $80\%$ n - heptane + $20\%$ n-octane
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Petrol, which has octane number 80 contain 20% n-heptane and 80% iso-octane.

Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

Synthetic petrol and kerosine can be made form coal by passing one of the following gases under heat and pressure over-coal.

  1. Nitrogen

  2. Hydrogen

  3. Oxygen

  4. Carbon dioxide
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

When coal is passed through hydrogen under heat and pressure it produces synthetic petrol and kerosene which is used for household fuel.