Exams › JEE Main › Chemistry

Read the assertion and reason below. Assertion (A): Boron cannot form the BF6³- ion. Reason (R): The atomic size of boron is very small. Choose the correct option.

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

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

Solution

Boron's small size (and absence of accessible d-orbitals) restricts it to a coordination number of at most 4, so BF6³- cannot form; the reason correctly explains the assertion.

Related JEE Main Chemistry questions

• Which of the following arrangements shows the decreasing order of acidic nature?
• Which one of the following oxides shows amphoteric behaviour?
• In boric acid (H₃BO₃), the hybridization 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
• Because the ns² electrons of the valence shell do not readily take part in bonding, which statement is correct?

⚔️ Practice JEE Main Chemistry free + battle 1v1 →