Question
Apart from tetrahedral geometry, another possible geometry for $C H _{ 4 }$ is square planar with the four H atoms at the corners of the square and the $C$ atom at its centre. Explain why $C H _{ 4 }$ is not square planar?
✓
Answer
The tetrahedral and square planar structure of methane is as follows :
According to VSEPR theory, the arrangement of electron pair around central atom should be in such a way that repulsion between them is minimum.
In square planar structure the bond angle is $90^{\circ}$ whereas in tetrahedral arrangement bond angle is $109^{\circ} 28^{\prime}$ due to which repulsion in tetrahedral structure is less as compared to the square planar. Therefore geometry of $CH _4$ is not square planar but tetrahedral.
According to VSEPR theory, the arrangement of electron pair around central atom should be in such a way that repulsion between them is minimum.
In square planar structure the bond angle is $90^{\circ}$ whereas in tetrahedral arrangement bond angle is $109^{\circ} 28^{\prime}$ due to which repulsion in tetrahedral structure is less as compared to the square planar. Therefore geometry of $CH _4$ is not square planar but tetrahedral.
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