Tag: coal and its products

Questions Related to coal and its products

Lignite is:

  1. high moisture and ash content coal

  2. low moisture and ash content

  3. has the highest heating value and lowest moisture

  4. the hardest type of coal,


Correct Option: A
Explanation:

Lignite is brownish-black in color and has a carbon content around 60–70 percent, a high inherent moisture content sometimes as high as 75 percent, and an ash content ranging from 6–19 percent compared with 6–12 percent for bituminous coal.

Which of the following type of coal is having lowest carbon content and heating value.

  1. anthracite

  2. bituminous

  3. lignite

  4. all of them


Correct Option: C
Explanation:

 A brownish-black coal with generally high moisture and ash content, and the lowest carbon content and heating value is lignite.

What chemical reaction makes biodiesel?

  1. transesterification

  2. sublimation

  3. polymerization

  4. fermentation


Correct Option: A
Explanation:
Sublimation is the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase.

Polymerization is a process of reacting monomer molecules together in a chemical reaction to form polymer chains.

The chemical breakdown of a substance by bacteria, yeasts, or other microorganisms, typically involving effervescence and the giving off of heat is called fermentation.

Transesterification is the process of exchanging the organic group R″ of an ester with the organic group R′ of an alcohol.
The alcohol reacts with the fatty acids to form the mono-alkyl ester (biodiesel) and crude glycerol.

Biodiesel production is the process of producing the biofuel, biodiesel, through the chemical reactions transesterification and esterification. This involves vegetable or animal fats and oils being reacted with short-chain alcohols (typically methanol or ethanol).

Which is the primary state in transformation of coal?

  1. Peat

  2. Bitumen

  3. Anthracite

  4. Lignite


Correct Option: A
Explanation:

The process of conversion of lignite to anthracite is called coalification or metamorphism of coal.
Coal is classified on the basis of its rank. The rank of coal denotes its degree of maturity. Vegetable matter, under the action of pressure, heat and anaerobic conditions, gets converted into different stages of coal namely:
Wood → Peat → lignite → sub-bituminous coal → bituminous coal → anthracite.
Peat is the first stage in the formation of coal.

The calorific value of lignite is about _____ kJ/g.

  1. 90 

  2. 78 

  3. 87 


Correct Option: D
Explanation:

The calorific value of the fuel is also called as the heat value of the fuel. It is defined as the amount of heat released by burning of unit quantity of the fuel. The calorific value is an important characteristic of the fuel. The unit of measurement of the calorific value is the same as the energy.

plant coal have a Calorific Value in the range of 9500 kJ/kg to 27000 kJ/ kg i.e 95 to 27 KJ/gm
The calorific value ranges from 8000 kJ/kg to 15000 kJ/kg i.e 8 to 15 KJ/gm.

Select the correct statement from the given:

  1. Peat is the most abundant rank of coal

  2. Peat has a heating value between 8300 and 13000 British Thermal Units per pound on a mineral-matter-free basis.

  3. Peat is an organic sediment.

  4. Peat has a carbon content of between 60 and 70%


Correct Option: C
Explanation:

The rank of coal is based on the degree to which the original plant material has been transformed into carbon.

The ranks are as follows:
(i) Anthracite (ii) Bituminous coal (iii) Sub-bituminous coal (iv) Lignite
Peat is mainly composed of wetland vegetation. Therefore, principally bog plants including mosses, sedges and shrubs. So, it is organic sediment.

Which among the following coal contains highest $\%$ of Carbon?

  1. Peat

  2. Bituminous

  3. Anthracite

  4. Lignite


Correct Option: C
Explanation:

The rank of coal is based on the amount of the plant converted into carbon.

Based on this four types of coal are generated:-
(i) Anthracite= $90$% carbon
(ii) Bituminous= $70$% carbon
(iii) Lignite= $40$% carbon
(iv) Peat= $28$% carbon
Anthracite has highest % of carbon.

The highest grade of coal, whose surface is shining and has the highest calorific value, is:

  1. bituminous

  2. peat

  3. anthracite

  4. lignite


Correct Option: C
Explanation:
Due to highest carbon content and fewest impurities, anthracite is the highest grade of coal, whose surface is shining and has the highest calorific value.

The energy of a neutron released during a fission process should be reduced by about ______ part to convert it into a thermal neutron.

  1. $10^8$

  2. $10^9$

  3. $10^6$

  4. $10^2$


Correct Option: A
Explanation:
 $10^8$
Thermal neutron, any free neutron (one that is not bound within an atomic nucleus) that has an average energy of motion (kinetic energy) corresponding to the average energy of the particles of the ambient materials. Relatively slow and of low energy, thermal neutrons exhibit properties, such as large cross sections in fission, that make them desirable in certain chain-reaction applications. Furthermore, the long de Broglie wavelengths of thermal neutrons make them valuable for certain applications of neutron optics. Thermal neutrons are produced by slowing down more energetic neutrons in a substance called a moderator after they have been ejected from atomic nuclei during nuclear reactions such as fission.

Which of the following is an optional form of energy ?

  1. Natural gas

  2. Hydrogen

  3. Petroleum

  4. Geothermal energy


Correct Option: D
Explanation:

Geothermal energy.

Geothermal energy is the heat from the Earth. It is clean and sustainable. Resources of geothermal energy range from the shallow ground to hot water and hot rock found a few miles beneath the Earth's surface, and down even deeper to the extremely high temperatures of molten rock called magma.