Tag: chemistry

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Questions Related to chemistry

Multiple choice chemistry rocks and minerals coal and its products study of coal coal

The density of coal is _______ when compared to coke.

  1. more

  2. less

  3. same

  4. can't say anything
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Coal is a naturally available substance whereas Coke is prepared substance  with some  impurities and high Carbon content, usually made from Coal.While Coal is Solid mass in physical appearance, Coke is Porous ( it means that it has large surface area ).

So the density of coal is more than the coke as coke is porous which has large surface area.

Hence option A is correct.

Multiple choice chemistry rocks and minerals coal and its products study of coal coal

Peat is the first stage product of coal consisting of _____ carbon.

  1. 20%

  2. 60%

  3. 35%

  4. 80%
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Peat is  first stage of transformation. Which contains 60% carbon and impurities like sufficient volatile matter and lot of moisture. It burns like wood, gives less heat, emits more smoke and leaves a lot of ash.

Multiple choice chemistry rocks and minerals coal and its products study of coal coal

Coal is a substance mainly containing carbon also having oxygen, hydrogen, nitrogen and _______.

  1. sodium

  2. sulphur

  3. aluminium

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

Coal is the substance composed of mainly carbon. Hydrogen, nitrogen, sulfur, and oxygen also present as impurities. Anthracite has the most carbon, while lignite is the lowest in carbon, but highest in hydrogen and oxygen.

Multiple choice chemistry rocks and minerals coal and its products study of coal coal

Which of the following fraction of coal tar distillation is obtained at 270° - 360°C?

  1. Light Oil

  2. Middle oil

  3. Green Oil

  4. All of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Green oil is obtained at 270° - 360°C by distillation of coal tar. It mainly has anthracene and phenanthrene. 

So, the correct option is $C$
Multiple choice chemistry rocks and minerals coal and its products study of coal coal

Ratio of primary air to secondary air increases with increase in the rank of coal, because the:

  1. ratio of fixed carbon to volatile matter increases

  2. high rank coals have higher amount of volatile matter

  3. calorific value of the coal increases

  4. oxygen content progressively decreases
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ratio of primary air to secondary air increases with increase in the rank of coal because the ratio of fixed carbon to volatile matter increases.

Multiple choice chemistry rocks and minerals coal and its products study of coal coal

The organic compound obtained from coal is/are:

  1. benzene and phenol

  2. naphthelene

  3. anthracene

  4. all of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Most of the carbon structures in the organic part of the coal are “alkylaromatics”, that is aromatic cores with aliphatic appendages like benzene, naphthelene and anthracene.
coal is heated in several different processes, all of which produce gases, liquids, asphaltic solids, and crude carbon charcoal. These are processed furthur to give several industrial products, invariably consisting of inseparable mixtures of organic compounds.

Multiple choice chemistry rocks and minerals coal and its products study of coal coal

Naphthalene balls used to repel moths and other insects are obtained from X. These days Y, a petroleum product, is used in place of X for metalling the roads. What are X and Y respectably?

  1. Coke, coal

  2. Coal, coke

  3. Bitumen, coal tar

  4. Coal tar, bitumen
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Napthalene balls used to repel moth and other insects are also obtained from coal tar. These days Bitumen, a petroleum product is used in place of coal tar for metalling roads. The gases present in coal gas are combustible.

Multiple choice chemistry rocks and minerals coal and its products study of coal coal

The residue left behind after the dry distillation of coal _____________.

  1. coal tar

  2. coal gas

  3. coke

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

When substances of vegetable origin, e.g. coal, oil shale, peat or wood, are heated in the absence of air (dry distillation), they decompose into gas, liquid products and solid residue coke/charcoal.

Multiple choice chemistry rocks and minerals coal and its products study of coal coal

The fractional distillation of coal tar yields:

  1. carbon disulphide

  2. carbon tetrachloride

  3. kerosene oil

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

Coal tar is the destructive distillation of bituminous coal. Coal tar is distilled into many fractions to yield a number of useful organic products like benzene, toluene, xylene, naphthalene, anthracene, etc.

Multiple choice chemistry rocks and minerals coal and its products study of coal coal

Which of the following contains methane, hydrogen and carbon dioxide?

  1. Producer gas

  2. Water gas

  3. Coal gas

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

Generally coal mine and coal gas contain Carbon monoxide, carbon dioxide, methane, oxygen, nitrogen, hydrogen, and other hydrocarbons.