Exams › JEE Main › Chemistry

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Melting point of Boron (2453 K) is unusually high in group 13 elements. Reason (R) : Solid Boron has very strong crystalline lattice. In the light of the above statements, choose the most appropriate answer from the options given below : (1) Both (A) and (R) are correct but (R) is not the correct explanation of (A) (2) Both (A) and (R) are correct and (R) is the correct explanation of (A) (3) (A) is false but (R) is true (4) (A) is true but (R) is false

1. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
2. Both (A) and (R) are correct and (R) is the correct explanation of (A)
3. (A) is false but (R) is true
4. (A) is true but (R) is false

Correct answer: Both (A) and (R) are correct and (R) is the correct explanation of (A)

Solution

The assertion is true because Boron has a high melting point compared to other group 13 elements, and the reason is also true as the strong crystalline lattice structure of solid Boron contributes to its high melting point, making the reason a valid explanation for the assertion.

Related JEE Main Chemistry questions

• Which of the following arrangements shows the decreasing order of acidic nature?
• Which of the following sequences correctly arranges Al₂O₃, SiO₂, P₂O₃ and SO₂ in increasing acid strength?
• Which one of the following oxides shows amphoteric behaviour?
• In boric acid (H₃BO₃), the hybridisation states of the boron atom and the oxygen atoms are, respectively,
• A xenon fluoride compound contains 53.5% xenon by mass. What oxidation state does xenon have in this compound?
• For a cement of good quality, what should be the approximate ratios of the following? I. Silica to alumina II. CaO to the combined oxides of SiO2, Al2O3 and Fe2O3

⚔️ Practice JEE Main Chemistry free + battle 1v1 →