Answer:
Sulfate = tetrahedral
Step-by-step explanation:
N° 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) 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
c) Chlorate = ClO3-
In ClO3-, the central atom is a Chlorine.
It has 7 valence electrons. The three oxygen form a double bond giving three bond pairs. The remaining two electrons make a lone pair. The total of 4 electron pairs shows that the molecule is sp3 hybridised.
The shape of sp3 hybrid molecule is a tetrahedral. But there is a lone pair. So, the geometry is pyramidal.
⇒AX4
⇒ bond angles = 190.5°
⇒Coordination number = 3
⇒pyramidal
Diffference between tetrahedral and pyramidal is that tetrahedral no has a lone pair, and has 4 atoms bonded to the central atom, while pyramidal has 1 lone pair and 3 atoms bonded to the central atom.
Sulfate has a tetrahedral geometry, which is a pyramidal structure