JEE Main 2022 · 27 Jul · Shift 2 · Chemistry Q68

ChemistrySingle correct+4 / -1Question 68 of 90

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) : Boron is unable to form $\mathrm{BF_6^{3-}}$ .

Reason (R) : Size of B is very small.

In the light of the above statements, choose the correct answer from the options given below :

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

Both (A) and (R) are true but (R) is not the correct explanation of (A)

(A) is true but (R) is false

(A) is false but (R) is true

Answer and worked solution

Official answer: B

Assertion. True: boron has no d orbitals, so its covalency stops at 4 ( $\mathrm{BF_4^-}$ ).

Reason. True (B is small), but the explanation is the absence of d orbitals.

(B)

Topics:Group 13

JEE Main 2022 · 27 Jul · Shift 2, Chemistry question 68