Question

$ClF_{3}$ is T-shape molecule while $NF_{3}$ has a trigonal pyramidal shape. Explain.

Answer 1

In $Cl{ F }_{ 3 }$ molecule, chlorine is central atom.  

The electronic configuration of chlorine is ${ 1s }^{ 2 }{ 2s }^{ 2 }{ 2p }^{ 6 }{ 3s }^{ 2 }{ 3p }^{ 5 }$.

The chlorine atom has five electrons and also it have five electron pairs among these three are bond pairs and two are lone pairs. It is a ${ AX }_{ 3 }{ L }_{ 2 }$ type molecule.

In $N{ F }_{ 3 }$ , nitrogen atom is central atom. The electronic configuration of fluorine is ${ 1s }^{ 2 }{ 2s }^{ 2 }{ 2p }^{ 5 }$.  

$N{ F }_{ 3 }$ is $AX_{ 3 }L$ type molecule and has Trigonal pyramidal shape.