Question

Which of the following sets contain isostructural molecules? I. \[ H_2O,\ OF_2,\ SCl_2 \] II. \[ CO_2,\ BeCl_2,\ HgCl_2 \] III. \[ SiCl_4,\ SF_4,\ XeF_4 \]

• A. I, II, III
• B. I, III only
• C. II, III only
• D. I, II only

Hint:

Common molecular shapes: \[ AX_2E_2 \rightarrow \text{Bent} \] \[ AX_2 \rightarrow \text{Linear} \] \[ AX_4 \rightarrow \text{Tetrahedral} \] \[ AX_4E \rightarrow \text{Seesaw} \] \[ AX_4E_2 \rightarrow \text{Square Planar} \] Molecules having the same shape are called isostructural.

Answer 1

The Correct Option is D

Concept: Isostructural molecules possess the same molecular geometry (shape).

Set I: \[ H_2O \] Central atom O has \[ AX_2E_2 \] configuration. Shape: Bent (V-shaped) \[ OF_2 \] also has \[ AX_2E_2 \] configuration. Shape: Bent \[ SCl_2 \] also has \[ AX_2E_2 \] configuration. Shape: Bent Hence, \[ \boxed{\text{Set I is isostructural}} \]

Set II: \[ CO_2 \] has \[ AX_2 \] geometry. Shape: Linear \[ BeCl_2 \] has \[ AX_2 \] geometry. Shape: Linear \[ HgCl_2 \] is also \[ \text{Linear}. \] Therefore, \[ \boxed{\text{Set II is isostructural}} \]

Set III: \[ SiCl_4 \] has \[ AX_4 \] geometry. Shape: Tetrahedral \[ SF_4 \] has \[ AX_4E \] geometry. Shape: Seesaw \[ XeF_4 \] has \[ AX_4E_2 \] geometry. Shape: Square planar Since the shapes are different, \[ \boxed{\text{Set III is not isostructural}} \]

Final Result: Only Sets I and II contain isostructural molecules. \[ \boxed{\text{I, II only}} \] \[ \boxed{\text{Answer = (D)}} \]