The bond angles marked a,b,and c in the molecule below are about ________,________,and ________,respectively.
A)109.5°, 109.5°, 109.5°
B)120°, 109.5°, 120°
C)109.5°, 109.5°, 120°
D)90°, 180°, 90°
E)109.5°, 109.5°, 90°

Question

The bond angles marked a,b,and c in the molecule below are about ________,________,and ________,respectively. 
A)109.5°, 109.5°, 109.5° 
B)120°, 109.5°, 120° 
C)109.5°, 109.5°, 120° 
D)90°, 180°, 90° 
E)109.5°, 109.5°, 90°

Quizplus · Accepted Answer

The molecule shown is trigonal bipyramidal. The angles between the axial atoms and the central atom (marked a) are 90°, while the angles between the equatorial atoms and the central atom (marked b) are 120°. The angles between the two sets of equatorial atoms (marked c) are also 120°. Therefore, the best choice is option C, which lists these angles correctly.

The Bond Angles Marked A,b,and C in the Molecule Below