Solved UPSC CDS/OTA Question
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Q · Mineralsmedium · 45s
Which mineral is the softest on the Mohs hardness scale?
TopicMinerals
Question Typemultiple choice
Difficultymedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Talc ranks as 1 on the Mohs hardness scale, making it the softest mineral. Composed of magnesium silicate [Mg₃Si₄O₁₀(OH)₂], talc has a greasy feel and can be easily scratched with a fingernail. Its softness and chemical inertness make it valuable in cosmetics, pharmaceuticals, ceramics, and as a lubricant in various industrial applications.
Final Answer: Option A - Talc