Tag: biology

Questions Related to biology

What chemical reaction makes biodiesel?

biology coal, petroleum and petrochemicals carbon cycling mineral coal carbon cycle coal and its products

  1. transesterification

  2. sublimation

  3. polymerization

  4. fermentation

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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?

biology coal, petroleum and petrochemicals carbon cycling mineral coal carbon cycle coal and its products

  1. Peat

  2. Bitumen

  3. Anthracite

  4. Lignite

Show answer
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.

biology coal, petroleum and petrochemicals carbon cycling mineral coal carbon cycle coal and its products

  1. 90 

  2. 78 

  3. 87 

  4. 8 

Show answer
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:

biology coal, petroleum and petrochemicals carbon cycling mineral coal carbon cycle coal and its products

  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%

Show answer
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?

biology coal, petroleum and petrochemicals carbon cycling mineral coal carbon cycle coal and its products

  1. Peat

  2. Bituminous

  3. Anthracite

  4. Lignite

Show answer
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:

biology coal, petroleum and petrochemicals carbon cycling mineral coal carbon cycle coal and its products

  1. bituminous

  2. peat

  3. anthracite

  4. lignite

Show answer
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.

biology carbon cycling mineral coal carbon cycle coal and its products coal petroleum and petrochemicals

  1. $10^8$

  2. $10^9$

  3. $10^6$

  4. $10^2$

Show answer
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 ?

biology carbon cycling mineral coal carbon cycle coal and its products coal petroleum and petrochemicals

  1. Natural gas

  2. Hydrogen

  3. Petroleum

  4. Geothermal energy

Show answer
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.

How much energy is produced when two$ _1H^2$ nuclei fuse to produce $ _1H^3$ and $ _1H^1$ ?

biology carbon cycling mineral coal carbon cycle coal and its products coal petroleum and petrochemicals

  1. 1.0 MeV

  2. 4.0 MeV

  3. 1000 MeV

  4. 3.3 MeV

Show answer
Correct Option: B
Explanation:
$4.0 MeV$
Energy released in most nuclear reactions is much larger than in chemical reactions, because the binding energy that holds a nucleus together is far greater than the energy that holds electrons to a nucleus. For example, the ionization energy gained by adding an electron to a hydrogen nucleus is $13.6 eV$—less than one-millionth of the $17.6 MeV$ released in the deuterium–tritium (D–T) reaction.  The complete conversion of one gram of matter would release $9\times10^{13}$ joules of energy. Fusion reactions have an energy density many times greater than nuclear fission; the reactions produce far greater energy per unit of mass even though individual fission reactions are generally much more energetic than individual fusion ones, which are themselves millions of times more energetic than chemical reactions. Only direct conversion of mass into energy, such as that caused by the annihilatory collision of matter and antimatter, is more energetic per unit of mass than nuclear fusion.

Properties of one of the mineral coal is given below. Identify the mineral coal.
(1) It is a matured form of mineral coal. 

(2) It contains 94% to 98% carbon.
(3) Its heat energy is about $33\, kJ \,gram^{-1}$

biology coal, petroleum and petrochemicals carbon cycling mineral coal carbon cycle coal and its products

  1. Bituminous Coal

  2. Lignite

  3. Peat

  4. Anthracite

Show answer
Correct Option: D
Explanation:

The mineral coal with given properties is Anthracite.

Anthracite is coal of a hard variety and contains relatively pure carbon and burns with little flame and smoke. The carbon content is highest. Very few impurities are present. The energy density is highest in Anthracite when compared to all types of coal except for graphite. Anthracite has the highest ranking of coal.