Rank these materials in order of increasing hardness: bituminous coal, peat, lignite, and anthracite coal.
Peat
Lignite
Bituminous coal
Anthracite coal
Yes, you're right.
To rank these materials in order of increasing hardness, we need to understand the concept of the Mohs hardness scale. The Mohs hardness scale measures the hardness of minerals based on their ability to scratch one another.
To determine the hardness of the materials provided, you can refer to their respective properties on the Mohs hardness scale. The scale ranges from 1 (for the softest minerals) to 10 (for the hardest minerals).
Here's how to rank the materials in order of increasing hardness:
1. Peat - Peat is the softest material on the list, so it has a low hardness value of around 1 on the Mohs scale. It is a type of decomposed vegetation found in boggy areas.
2. Lignite - Lignite is a soft brown coal formed from peat. It has a slightly higher hardness than peat, typically ranging from 1 to 2 on the Mohs scale.
3. Bituminous coal - Bituminous coal is a widely used type of coal characterized by its relatively high carbon content. It is harder than peat and lignite, typically ranging from 2 to 3 on the Mohs scale.
4. Anthracite coal - Anthracite coal is the hardest type of coal. Due to its high carbon content and strong metamorphic pressure, it has a hardness of around 2.5 to 3.5 on the Mohs scale.
Therefore, the ranking from least to most hardness is:
Peat, Lignite, Bituminous coal, Anthracite coal.