JEE · NEET Previous Year Question
Statement I: Boron does not exhibit allotropy
Statement II: Boron is extremely hard and black coloured solid
Topic: JEE PYQ
Answer: D. Full step-by-step solution below.
- ABoth I & II are correct
- BBoth I & II are not correct
- C is correct but II is not correct
- DI is not correct but II is correct
Correct answer: D
Solution
(d) Boron exists in crystalline and amorphous allotropes like - and - rhombohedral and -tetragonal allotrope. Thus, I is not correct. Boron is extremely hard and black-coloured solid and high-melting due to high crystal lattice enthalpy. Thus, II is correct.More s-Block Elements PYQs
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