Geometry of XeOF4 by VSEPR theory:

The VSEPR (Valence Shell Electron Pair Repulsion) theory is a model used in chemistry to predict the shape of molecules based on the repulsion between electron pairs in the valence shell of an atom. According to this theory, the geometry of XeOF4 is square pyramidal. Let's understand why.

1. Determine the central atom:
In XeOF4, the central atom is Xenon (Xe).

2. Count the total number of valence electrons:
Xenon (Xe) belongs to Group 8A in the periodic table, so it has 8 valence electrons. Oxygen (O) belongs to Group 6A, so each oxygen atom contributes 6 valence electrons. Additionally, there are four fluorine (F) atoms, each contributing 7 valence electrons. Therefore, the total number of valence electrons in XeOF4 is:

(1 x 8) + (4 x 6) + (4 x 7) = 8 + 24 + 28 = 60

3. Determine the electron pair arrangement:
To determine the electron pair arrangement, we need to consider both the bonding and non-bonding pairs of electrons around the central atom.

In XeOF4, Xenon is bonded to one oxygen atom and four fluorine atoms. The oxygen atom forms a double bond with Xenon, using two pairs of electrons. Each fluorine atom is bonded to Xenon by a single bond, contributing one pair of electrons each. This gives a total of 2 + 4 = 6 bonding pairs of electrons.

4. Determine the molecular geometry:
To determine the molecular geometry, we need to consider the positions of the bonding and non-bonding electron pairs around the central atom.

In XeOF4, the bonding pairs of electrons repel each other and try to get as far away from each other as possible. The repulsion between these electron pairs results in the square pyramidal shape. The oxygen atom occupies one of the vertices of the square pyramid, and the four fluorine atoms occupy the other four vertices.

Therefore, the geometry of XeOF4 according to the VSEPR theory is square pyramidal.

Overall, the VSEPR theory provides a useful framework for predicting molecular shapes based on the repulsion between electron pairs. By applying this theory, we can determine the geometry of XeOF4 as square pyramidal.