Arrange the following molecules in the correct order of their bond angles:
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Remember the structures and bond angles of these common allotropes:
- White Phosphorus (\(P_4\)): A highly strained tetrahedron with 60° angles.
- Sulfur (\(S_8\)): The stable form is a crown-shaped ring with ~108° angles.
- Sulfur (\(S_6\)): A less stable chair-shaped ring with ~102° angles.
The smaller the ring, the greater the angle strain and the smaller the bond angle for these non-planar rings.
To determine the correct order of bond angles among the molecules given: S8 (A), P4 (B), S6 (C), and O3 (D), let's analyze each molecule.
S8 (A): S8 is a crown-shaped molecule where the sulfur atoms form a puckered ring. The bond angles are approximately 108 degrees, close to the tetrahedral angle due to the bent structure of each S-S-S angle around the ring.
P4 (B): P4 forms a tetrahedral shape where each bond angle is about 60 degrees due to the small, tetrahedral cage structure with P atoms at the vertices.
S6 (C): S6 has a chair-like conformation similar to cyclohexane, with bond angles also close to 102 to 107 degrees, slightly varying due to the chair conformational stress.
O3 (D): Ozone has a bent/angular shape with a bond angle of approximately 117 degrees due to the lone pair-lone pair repulsion which reduces the angle from the typical 120 degrees seen in trigonal planar structures.
The order of increasing bond angles is:
B (P4, ~60 degrees)
C (S6, ~102-107 degrees)
A (S8, ~108 degrees)
D (O3, ~117 degrees)
Thus, the correct order is B < C < A < D, which matches option B < C < A < D.
