Tag: coal

Questions Related to coal

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

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

  1. sodium

  2. sulphur

  3. aluminium

  4. chlorine

Show answer
Correct Option: B
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.

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

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

  1. Light Oil

  2. Middle oil

  3. Green Oil

  4. All of the above

Show answer
Correct Option: C
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 $C$

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

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

  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

Show answer
Correct Option: A
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.

The organic compound obtained from coal is/are:

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

  1. benzene and phenol

  2. naphthelene

  3. anthracene

  4. all of the above

Show answer
Correct Option: D
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.

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?

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

  1. Coke, coal

  2. Coal, coke

  3. Bitumen, coal tar

  4. Coal tar, bitumen

Show answer
Correct Option: D
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.

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

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

  1. coal tar

  2. coal gas

  3. coke

  4. ammonia liquor

Show answer
Correct Option: C
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.

The fractional distillation of coal tar yields:

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

  1. carbon disulphide

  2. carbon tetrachloride

  3. kerosene oil

  4. benzene

Show answer
Correct Option: D
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.

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

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

  1. Producer gas

  2. Water gas

  3. Coal gas

  4. Bio gas

Show answer
Correct Option: C
Explanation:

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

Which one of the following substances can be used both as a fuel and a reducing agent?

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

  1. Coke

  2. Wood

  3. Methane

  4. Methyl alcohol

Show answer
Correct Option: A
Explanation:

Coke can be used both as a fuel and a reducing agent. The combustion of coke (carbon) is highly exothermic and releases a huge amount of energy. Hence, coke is a fuel. Carbon itself is easily oxidized to $CO$ and $CO _2$. $C$ can easily reduce several metal oxides to metal.

When steam is passed over hot coke, it produces:

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

  1. producer synthesis gas

  2. synthesis gas

  3. tear gas

  4. coal gas

Show answer
Correct Option: B
Explanation:

Syngas or synthesis gas is a fuel gas mixture consisting primarily of H, CO and very small carbon dioxide. The reaction between coke and steam is highly endothermic and when the coke bed is cooled to a normal temperature the steam is replaced by a blast of air.