Solved Questions on Coal and Petroleum
1. To investigate the process of fractional distillation of petroleum, a student sets up a distillation apparatus with a fractional distillation column. What is the purpose of the fractional distillation column in this setup?
a) To heat the petroleum to its boiling point
b) To separate the different components of petroleum-based on their boiling points
c) To cool down the petroleum after distillation
d) To measure the volume of the distilled petroleum
Answer: b) The fractional distillation column works on the principle that different components of petroleum have different boiling points. As heated petroleum vapour rises up the column, it cools down, and the components with higher boiling points condense and settle at different heights in the column. This process results in the separation of various fractions of petroleum-based on their boiling points, allowing the collection of different products at different levels of the column.
2. Consider the following statements and choose the correct option:
Statement 1: Coal gas is a mixture of hydrogen, carbon monoxide, methane, and other gases.
Statement 2: Coal gas is obtained during the processing of coal to get coke.
a) Statement 1 is correct but statement 2 is incorrect.
b) Statement 1 is incorrect but statement 2 is correct.
c) Both statements are correct.
d) Both statements are incorrect.
Answer: a) Statement 1 is correct as coal gas is indeed a mixture of hydrogen, carbon monoxide, methane, and other gases. However, statement 2 is incorrect because coal gas is obtained during the process of destructive distillation of coal, not during the processing of coal to get coke.
3. In the following question, you will find an assertion and a reason. Select the appropriate option that applies.
Assertion: Destructive distillation of coal produces various valuable products.
Reasoning: During the destructive distillation of coal, when coal is heated in the absence of air, it undergoes thermal decomposition, resulting in the formation of coke, coal tar, and coal gas. These products have multiple industrial applications.
a) Both the assertion and reasoning are correct, and the reasoning is the correct explanation of the assertion.
b) Both the assertion and reasoning are correct, but the reasoning is not the correct explanation of the assertion.
c) The assertion is correct, but the reasoning is incorrect.
d) Both the assertion and reasoning are incorrect.
Answer: a) Both the assertion and reasoning are correct, and the reasoning is the correct explanation of the assertion.
The assertion is correct because the destructive distillation of coal indeed produces valuable products like coke, coal tar, and coal gas. The reasoning is also correct because it explains that during destructive distillation, when coal is heated in the absence of air, it undergoes thermal decomposition, leading to the formation of these valuable products with various industrial applications.
4. Which of the following options correctly represents the order in which products are obtained during the refining of petroleum?
a) Bitumen, kerosene, petrol, petroleum gas
b) Petroleum gas, kerosene, petrol, bitumen
c) Kerosene, petrol, petroleum gas, bitumen
d) Petroleum gas, petrol, kerosene, bitumen
Answer: d) Petroleum gas, petrol, kerosene, bitumen
During the refining of petroleum through fractional distillation, the products are separated based on their boiling points. Petroleum gas, which has the lowest boiling point, is obtained at the top of the distillation column, followed by petrol, kerosene, and bitumen in descending order of their boiling points.
5. Which of the following is a correct characteristic of natural gas?
I: It is a solid fossil fuel.
II: It causes high pollution on combustion.
III: It consists mainly of methane.
IV: It is obtained from the destructive distillation of coal.
a) I, III, and IV
b) Only III
c) III and IV
d) II, III, and IV
Answer: b) Natural gas is a gaseous fossil fuel and consists mainly of methane, which is mentioned in statement III. It is not obtained from the destructive distillation of coal, so statement IV is incorrect. Statements I and II are incorrect as natural gas is not a solid fuel, and it causes less pollution on combustion compared to other fossil fuels.
FAQs
1. What is coal and how it is used?
Coal is a fossil fuel made from the remains of ancient plants that have been buried and exposed to high pressure and heat for millions of years. It is mostly made of carbon and is extracted from underground or surface mines. Coal is largely used to generate energy, where it is burned to produce steam that powers turbines that are linked to generators.
2. What are the different types of coal, and how do they differ?
Coal is divided into several categories based on its carbon concentration, moisture content, and heating value. The four primary kinds of coal are lignite, sub-bituminous, bituminous, and anthracite, with each having unique qualities and applications.
3. What are the benefits of using CNG and LPG as fuel?
The benefits of utilizing CNG and LPG as fuels include:
- Easy combustion: CNG and LPG burn readily.
- High heat output: When ignited, CNG and LPG produce substantial heat energy.
- Convenient transportation: Both CNG and LPG can be transported efficiently through pipelines.
- Clean burning: CNG and LPG are considered clean fuels as they emit minimal smoke when burned.
4. How do coal-fired power stations and oil refineries contribute to air pollution?
Coal-fired power plants generate pollutants such as sulfur dioxide, nitrogen oxides, and particulate matter, exacerbating air pollution and respiratory problems. Petroleum refineries emit volatile organic chemicals, sulfur compounds, and greenhouse gasses, aggravating air pollution.
5. How do coal and petroleum contribute to global energy consumption?
Coal and petroleum are major contributors to global energy consumption, accounting for a sizable part of power production, transportation fuel and industrial energy requirements globally.
