Tag: rocks and minerals

Quizzes (5) Questions (347)

Questions Related to rocks and minerals

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

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

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
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.

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

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
Reveal answer Fill a bubble to check yourself
B Correct answer
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.

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

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
Reveal answer Fill a bubble to check yourself
A Correct answer
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.

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

Which one is true for the octane number of following organic compounds?

  1. Aromatic Compound $>$ Aliphatic compound
  2. Aromatic compound $<$ Aliphatic compound
  3. Aromatic compound $=$ Aliphatic compound

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The octane number of a fuel is based on how fuels auto-ignite, under compression.
1. It is based on the scale where isooctane is 100 (minimal ignition under pressure) and heptane is 0 (easily ignites under pressure).
For example, petrol with an octane number of 92 has the same knock as a    mixture of 92% isooctane and 8% heptane.
2. Octane rating decreases with an increase in the carbon chain length.
3. Octane ratings increase with carbon chain branching.
4. Octane ratings increase in aromatics with the same number of carbons.

Hence, the correct option is $A$
Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

In steam cracking, initiation usually involves breaking a chemical bond between:

  1. carbon and hydrogen atom

  2. carbon atoms

  3. carbon-hydrogen and carbon-carbon simultaneously

  4. no bond is completely broken in initiation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In steam cracking, initiation usually involves breaking a chemical bond between two carbon atoms, rather than the bond between a carbon and a hydrogen atom.

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

Most of the chemical reactions in Cracking is based on:

  1. Carbocation formation

  2. Carbanion formation

  3. Radical formation

  4. Zwitter ion formation
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In cracking, the initial process involves the breaking down of hydrocarbons into free radicals.Only a small fraction of the feed molecules actually undergo initiation, but these reactions are necessary to produce the free radicals that drive the rest of the reactions.

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

Select the correct option about the Octane number of the organic compound.

  1. Saturated compound $>$ Unsaturated compound
  2. Saturated compound $<$ Unsaturated compound
  3. Saturated compound $=$ Unsaturated compound

  4. Both A and B
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

An unsaturated compound has a higher octane rating than a saturated compound.