Question

Two \(p\)-block elements \(X\) and \(Y\) form fluorides of the type \(EF_3\). The fluoride compound \(XF_3\) is a Lewis acid and \(YF_3\) is a Lewis base. The hybridizations of the central atoms of \(XF_3\) and \(YF_3\) respectively are

• A. Both \(sp^2\)
• B. Both \(sp^3\)
• C. \(sp^2\) and \(sp^3\)
• D. \(sp^3\) and \(sp^2\)

Hint:

Lewis acidic fluorides generally have electron-deficient central atoms, while Lewis basic fluorides contain lone pairs.

Answer 1

The Correct Option is C

Step 1: Analyze \(XF_3\).
Since \(XF_3\) is a Lewis acid, the central atom \(X\) has an incomplete octet and can accept an electron pair. Such fluorides are typically trigonal planar with no lone pair on the central atom, implying \[ \text{Hybridization of } X = sp^2. \] Step 2: Analyze \(YF_3\).
Since \(YF_3\) is a Lewis base, the central atom \(Y\) must have a lone pair available for donation. Thus, the central atom has three bond pairs and one lone pair, giving a tetrahedral electron geometry and \[ \text{Hybridization of } Y = sp^3. \] Final Answer: \[ \boxed{sp^2 \text{ and } sp^3} \]