Mohs scale is used to indicate which physical property of a mineral?

Introduction / Context:
Mohs scale is a standard reference used in geology and mineralogy to compare and classify minerals based on how easily they can be scratched. Questions about Mohs scale are common in general science and geography exams. The scale runs from one to ten, where talc is assigned a hardness of one and diamond is assigned a hardness of ten. The key idea is that Mohs scale measures hardness, not other properties such as brittleness, viscosity, elasticity, or magnetism.

Given Data / Assumptions:

• The term mentioned is Mohs scale.
• The question asks which physical property of minerals this scale indicates.
• Options include brittleness, hardness, viscosity, elasticity, and magnetism.
• No numerical calculation is needed; only conceptual knowledge is tested.

Concept / Approach:
Mohs scale of mineral hardness was created by Friedrich Mohs. It ranks minerals according to their ability to scratch another material or be scratched by it. For example, a mineral with Mohs hardness 7 can scratch minerals rated 6 or below, but not those rated higher. This ranking system helps geologists quickly identify minerals in the field. It does not measure brittleness, which is how easily a material breaks, nor viscosity, elasticity, or magnetic strength. Therefore, the correct association of Mohs scale is with the degree of hardness of a mineral.

Step-by-Step Solution:
Step 1: Recall that Mohs scale is specifically called the Mohs scale of hardness. Step 2: Remember the classic list of Mohs hardness from talc at 1 to diamond at 10. Step 3: Recognize that hardness here means resistance to scratching, not to breaking under impact. Step 4: Compare the options and identify the one that explicitly mentions hardness of a mineral. Step 5: Select “Degree of hardness of a mineral” as the correct answer.

Verification / Alternative check:
You can verify this by recalling field tests where a geologist uses a fingernail, a copper coin, a steel blade, or a glass plate to test whether a mineral can scratch or be scratched by those objects. These tests are based on Mohs hardness values. Additionally, many textbooks label the table with the heading “Mohs hardness scale” which clearly ties the term Mohs to hardness. No similar association exists between Mohs and viscosity, elasticity, or magnetism, confirming that hardness is the property in question.

Why Other Options Are Wrong:
Degree of brittleness of a substance: Brittleness describes how easily a material breaks or shatters, but Mohs scale does not classify minerals in this way.
Degree of viscosity of a liquid: Viscosity is related to how thick or runny a fluid is; Mohs scale is not applied to liquids at all.
Degree of elasticity of a material: Elasticity describes how a material stretches and returns to its original shape; again, Mohs scale does not measure this property.
Degree of magnetism of a metal: Magnetism is a separate physical property and is not part of the Mohs hardness classification.

Common Pitfalls:
Students sometimes confuse hardness with brittleness or strength. A mineral can be very hard yet brittle, meaning it can scratch other substances but may break easily if struck. Because of this, some learners mistakenly choose brittleness when they see Mohs scale. Others may vaguely remember Mohs as a measurement and randomly pick any physical property. To avoid this, remember the phrase Mohs hardness scale and connect it firmly with scratch resistance of minerals. This will help you instantly recognize the correct option in exams.

Final Answer:
Mohs scale is used to indicate the degree of hardness of a mineral.