Tag: rocks and minerals

Questions Related to rocks and minerals

Liquid hydrocarbons can be converted to a mixture of gaseous hydrocarbons by:

chemistry energy rocks and minerals petroleum and natural gas fossil fuels

  1. oxidation

  2. cracking

  3. distillation under reduced pressure

  4. hydrolysis

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Correct Option: B
Explanation:

The process of breaking higher hydrocarbons with high boiling points into a variety of lower hydrocarbons that are more volatile (low boiling), is called cracking (or pyrolysis). For example, a higher hydrocarbon $C _{10}H _{22}$ splits according to the reaction.

$C _{10}H _{22}  \xrightarrow {heat \ 770K} C _8H _{18} + C _2H _4$
The process of cracking or pyrolysis increases the relative amounts of the lower hydrocarbons, which exists in a gaseous state, while higher hydrocarbons exist in the liquid or solid state.

Process of conversion of wood into coal by biochemical process, taking over millions of years is called :

chemistry energy rocks and minerals petroleum and natural gas fossil fuels

  1. Catenation

  2. Carbonation

  3. Pyrolysis

  4. Destructive distillation

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Correct Option: B
Explanation:

Process of conversion of wood into coal by biochemical process over a millions of years is called carbonation.This process occurs in the deep level of earth.

Hence option B is correct.

Cracking is a process in which :

chemistry energy rocks and minerals petroleum and natural gas fossil fuels

  1. Petrol is produced by cracks on the surface of wax.

  2. Combustion of petrol is carried out.

  3. Compounds of high molecular mass are converted into compounds of lower molecular mass

  4. None of the statements is correct

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Correct Option: C

For grading diesel oil the term octane number is used.  

chemistry energy rocks and minerals petroleum and natural gas fossil fuels

  1. True

  2. False

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Correct Option: B

Straight chain hydrocarbons have high octane number values than branched-chain hydrocarbons. 

chemistry energy rocks and minerals petroleum and natural gas fossil fuels

  1. True

  2. False

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Correct Option: B

Octane number can be changed by :

chemistry energy rocks and minerals petroleum and natural gas fossil fuels

  1. alkylation

  2. cyclisation

  3. isomerisation

  4. All of these

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Correct Option: D
Explanation:

All the three reactions, i.e. alkylation, cyclisation, and isomerisation convert straight-chain hydrocarbons to branched-chain or cyclic compounds, which changes the percentage of straight-chain hydrocarbon. 


Hence, the octane number is changed.

So, the correct option is D.

Which of the following are not obtained on fractional distillation of petroleum?

chemistry energy rocks and minerals petroleum and natural gas fossil fuels

  1. Paraffin wax

  2. Asphalt

  3. Coal gas

  4. None of these

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Correct Option: C
Explanation:

Various fractions obtained during the fractional distillation of petroleum can be categorized into two viz, Petroleum products used as fuels: Petroleum gas, petrol, kerosene, diesel, fuel oil; Petroleum product not used as fuel:- Petroleum ether, greases, petroleum jelly, paraffin wax, pitch, asphalt.

So, Coal gas is not prepared using fractional distillation.

Breaking of higher hydrocarbon into lower one by heat is called:

chemistry energy rocks and minerals petroleum and natural gas fossil fuels

  1. neutralisation

  2. polymerisation

  3. cracking

  4. acetylating

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Correct Option: C
Explanation:

Cracking is defined as “the decomposition of high boiling hydrocarbons of high molecular weight into smaller low boiling hydrocarbons of low molecular weight”. Usually high boiling point hydrocarbons are liquids and low boiling point hydrocarbons are gases.

Which of the following is not required for the formation of coal?

chemistry energy rocks and minerals petroleum and natural gas fossil fuels

  1. Dead organisms

  2. Dead vegetation

  3. Presence of oxygen

  4. High pressure

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Correct Option: C
Explanation:

Carbonization of dead plants and animals does not happen in the presence of oxygen. This is the procedure which takes place inside the earth crust under high pressure and temperature.


 It is believed that millions of years ago, the ground below the forests was split open by natural forces such as earthquakes and volcanoes. 

The forests got buried under the surface of earth. Thus, the plants had no contact with oxygen. Successive layers of sediments sealed the buried plants. Over millions of year, these deposits were subjected to tremendous pressure and heat finally transformed them into coal.

Option C is correct.

What happens in carbonization process?

chemistry energy rocks and minerals petroleum and natural gas fossil fuels

  1. Hydrolysis

  2. Electrolysis

  3. Pyrolysis

  4. All of the above

Show answer
Correct Option: C
Explanation:

Carbonization is the term which means destructive distillation of coal which is done in the absence air in order to obtain coke and other fractions having greater percentage of carbon than the original material.


It is defined as the conversion of organic matter into carbon or the residues containing carbon through the process of pyrolysis or destructive distillation.

In the organic chemistry it is referred as the generation of coal gas or coal tar from raw coal materials.It is also applied to the pyrolysis of coal to produce coke and charcoal etc.

Option C is correct.