Tag: petroleum and natural gas

Questions Related to petroleum and natural gas

In case of straight chain hydrocarbons, the octane number increases with increase in the length of the chain.

  1. True

  2. False


Correct Option: B
Explanation:

In case of straight chain hydrocarbons, the octane number decreases with increase in the length of the chain.

The octane numbers of aromatic hydrocarbons are exceptionally low.

  1. True

  2. False


Correct Option: B
Explanation:

The octane numbers of aromatic hydrocarbons are exceptionally high.

Introduction of double or triple bond decreases the value of octane number.

  1. True

  2. False


Correct Option: B
Explanation:

Introduction of double or triple bond increases the value of octane number.

What is the octane number of $n$-nonane?

  1. 0

  2. $-20$

  3. 100

  4. more than 100


Correct Option: B
Explanation:

$n$-nonane has an octane number of $-20$.

Compounds with more than 100 and less than 0 octane numbers are not known.

  1. True

  2. False


Correct Option: B
Explanation:

Compounds with more than 100 and less than 0 octane numbers are  also known. For example triptane has octane number of 125 and n -nonane has octane number of -45.

Branching of chain decreases the value of octane number.

  1. True

  2. False


Correct Option: B
Explanation:

Branching of chain increases the value of octane number.

Which of the following will increase the octane number of gasolines?

  1. cracking

  2. alkylation

  3. isomerisation

  4. all of the above


Correct Option: D
Explanation:

Cracking, alkylation and isomerization will increase the octane number of gasolines.


 

The addition of which of the following will increase the octane number of gasoline?

  1. benzene

  2. toluene

  3. xylene

  4. all of the above


Correct Option: D
Explanation:

The addition of benzene, toluene and xylene will increase the octane number of gasoline.

During carbonisation or destructive distillation of coal, bituminous coal is heated in iron or fire clay retorts to high temperature (500 deg C) in presence of air.

  1. True

  2. False


Correct Option: B
Explanation:

During carbonization or destructive distillation of coal, bituminous coal is heated in iron or fireclay retorts to high temperature (1000-1400 deg C) in absence of air.

In cracking, reaction is propagated through:

  1. absorption of hydrogen by the formed radical

  2. release of hydrogen by the formed radical

  3. gain of electrons by the formed radical

  4. release of electron by formed radical


Correct Option: A
Explanation:

In propagation step of cracking process, a free radical removes a hydrogen atom from another molecule, turning the second molecule into a free radical.