Answer:
Nitrate has a planar molecular geometry
Explanation:
Number of electron groups Geometry Formula
2 linear AX2
3 trigonal-planar AX3 or AX2E
4 tetrahedral AX4/AX3E/AX2E2
a) Nitrate = NO3-
⇒ AX3
⇒ bond angles = 120°
⇒ Coordination number = 3
⇒ Trigonal planar
b) ammonium = NH4+
Nitrogen atom is at the center and three Hydrogen atoms are at three vertices. The lone pair on N points to the fourth vertice.
⇒AX4
⇒ bond angles = 190.5°
⇒Coordination number = 4
⇒Tetrahedral
c) Sulfate= SO42-
The central S
-atom has four electron domains. It has no lone pairs, so the electron geometry and the molecular geometry are tetrahedral.
⇒AX4
⇒ bond angles = 190.5°
⇒Coordination number = 4
⇒Tetrahedral
Option A, nitrate is the correct answer.
