The electron domain and molecular geometry of BrO2- is
A tetrahedral, bent
B. trigonal pyramidal, seesaw
C. trigonal pyramidal, linear
D. tetrahedral, trigonal planar
E. trigonal planar, trigonal planar
The Correct Answer and Explanation is :
The correct answer is:
A. Tetrahedral, Bent
Explanation:
- Lewis Structure of BrO₂⁻
- Bromine (Br) has 7 valence electrons.
- Oxygen (O) has 6 valence electrons (each).
- The negative charge (-1) adds one extra electron.
- Total valence electrons:
[
7 + (6 \times 2) + 1 = 19
] - Bromine is the central atom, bonded to two oxygens and has lone pairs.
- Electron Domains (VSEPR Theory)
- There are four electron domains around Br:
- Two bonding pairs (Br–O bonds)
- Two lone pairs
- This corresponds to a tetrahedral electron domain geometry.
- Molecular Geometry
- The molecular geometry is determined by the positions of atoms.
- The two lone pairs push the bonded oxygen atoms downward, creating a bent shape.
- This is similar to water (H₂O), which has a tetrahedral electron domain but a bent molecular shape.
- Bond Angles
- A perfect tetrahedral shape has 109.5° angles.
- However, lone pairs repel more strongly, slightly reducing the O–Br–O angle to less than 109.5°.
Conclusion:
- Electron Domain Geometry: Tetrahedral
- Molecular Geometry: Bent
Thus, the correct answer is A. Tetrahedral, Bent.
Now, I’ll generate an image of the molecular structure of BrO₂⁻.

Here is the 3D molecular structure of the bromite ion (BrO₂⁻), showing its tetrahedral electron domain geometry and bent molecular shape. Let me know if you need any modifications or further explanations!