The material ranking immediately above talc on the Mohs scale in terms of softness is___________________?
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Answer: B. Gypsum
Explanation
Gypsum has a defined Mohs hardness rating of two, placing it directly above talc at one. Its chemical structure consists of calcium sulfate dihydrate with relatively weak interlayer bonding. This specific hardness allows gypsum to be easily scratched by a copper fingernail coin equivalent. The Mohs scale ranks minerals from one representing talc up to ten representing diamond hardness. Gypsum is a soft sulfate mineral commonly mined for industrial plaster and drywall production. Friedrich Mohs selected ten reference minerals based on their scratch resistance characteristics.
Construction industries consume massive quantities of gypsum for manufacturing interior wallboard panels. Agricultural soils sometimes receive gypsum treatments to improve calcium nutrition and drainage properties. Sculptors and artisans use gypsum plasters to create detailed casts and decorative architectural moldings. Quartz is much harder with a Mohs rating of seven, placing it far above gypsum. Feldspar has a Mohs hardness rating of six, making it significantly harder than gypsum. Fluorite possesses a Mohs hardness rating of four, positioning it above gypsum on the scale.
- Subject
- Engineering
- Category
- Chemical Engineering
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- —
- Difficulty
- medium
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