JEE Main 2023 — Chemical Bonding And Molecular Structure Question with Solution

Let's consider each species in List I and determine their geometries/shapes.

A. ${\mathrm{H}}_3{\mathrm{O}}^{+}$: This ion is formed by the addition of a proton to a water molecule. The central atom (O) is surrounded by three Hydrogen atoms and one lone pair, making its shape pyramidal.

B. Acetylide anion: The acetylide ion (${\mathrm{C}}_2{\mathrm{H}}^{-}$ or ${\mathrm{C}}_2^{2-}$) has a linear geometry as the three atoms are in a straight line.

C. $\mathrm{N}{\mathrm{H}}_4^{+}$: The ammonium ion has a central nitrogen atom surrounded by four hydrogen atoms, giving it a tetrahedral geometry.

D. $\mathrm{Cl}{\mathrm{O}}_2^{-}$: The chlorite ion has a central chlorine atom surrounded by two oxygen atoms and one lone pair, which gives it a bent or V-shaped geometry.

Matching these to List II, we get:

A. ${\mathrm{H}}_3{\mathrm{O}}^{+}$ - III. Pyramidal

B. Acetylide anion - II. Linear

C. $\mathrm{N}{\mathrm{H}}_4^{+}$ - I. Tetrahedral

D. $\mathrm{Cl}{\mathrm{O}}_2^{-}$ - IV. Bent