Question

Arrange the following coal types in the increasing order of their heat content (KJ/kg)
(A). Peat
(B). Lignite
(C). Anthracite
(D). Bituminous
(E) Sub-bituminous
Choose the correct answer from the options given below:

• A. (A), (B), (C), (D), (E)
• B. (A), (B), (E), (D), (C)
• C. (C), (D), (E), (B), (A)
• D. (A), (B), (D), (E), (C)

Hint:

Remember the acronym \textbf{PLBAS} (for \textbf{P}eat, \textbf{L}ignite, \textbf{B}ituminous, \textbf{A}nthracite, \textbf{S}ub-bituminous is between L and B). The order in the acronym is from lowest quality (heat content) to highest, with Sub-bituminous fitting between Lignite and Bituminous.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
The heat content (calorific value) of coal is directly related to its rank or stage of formation (coalification). The longer the coal has been subjected to heat and pressure, the higher its carbon content and heat content. The question asks for the order from lowest to highest heat content.
Step 2: Detailed Explanation:
The ranks of coal from lowest to highest are:
1. (A) Peat: This is the precursor to coal. It has low carbon content, high moisture, and the lowest heat content.
2. (B) Lignite: Also known as brown coal, this is the lowest rank of coal. It has a higher heat content than peat.
3. (E) Sub-bituminous: This is the next rank up from lignite, with lower moisture and higher carbon content.
4. (D) Bituminous: This is a dense, black coal with a high heat content. It is the most abundant type of coal.
5. (C) Anthracite: This is the highest rank of coal. It has the highest carbon content, the lowest moisture, and the highest heat content.
Step 3: Final Answer:
The correct increasing order of heat content is Peat<Lignite<Sub-bituminous<Bituminous<Anthracite. This corresponds to the sequence (A), (B), (E), (D), (C).