________________ stands out as the hardest substance among those listed ?
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Answer: A. Boron carbide
Explanation
Boron carbide features a rigid covalent crystal structure with extreme atomic bond strength. This robust chemical bonding gives it exceptional resistance to scratching and indentation. It stands out as the hardest synthetic substance among the provided options. Superhard materials are utilized for demanding abrasive and armor applications. Hardness scales measure a material resistance to localized surface plastic deformation. Synthetic carbides are manufactured at very high temperatures in electric furnaces.
Boron carbide is used in blast nozzles, bulletproof vests, and abrasive grinding wheels. Industrial cutting tools benefit from coatings that resist extreme abrasive wear. Material hardness determines suitability for high-impact and wear-intensive tasks. Tungsten carbide is extremely tough but softer than boron carbide materials. Hardened steel is used for tools but ranks far below advanced synthetic carbides. Silicon carbide is hard and abrasive but less hard than boron carbide.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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