Interpret the non-linear shape of `H_(2)S` molecule and non-planar shape of `PCl_(3)` using valence shell electron pair repulsion (VSEPR) theory.
(Atomic number `:H=1, P=15, S=16, Cl=17`)

Explanation

In `H_(2) O ` atomic number of central atom (S) = 16
Electronic arrangment of S = 2, 8, 6
Out of 6 valence eletrons , two electrons are shared with two H atoms and the remaining four electrons are
present as two lone pairs . Thus, we hgave

i.e., it is a molecule of the type `AB_(2)L_(2)` . Due to repulsions between bond pairs and lone pairs the shape is
bent (non-linear).
In `PCl_(3)` atomic number of central atom (P) = 15
Electronic arrangement of P = 2, 8, 5
Out of 5 valence eleectrons , three electrons are shared with three Cl atoms and the remaining 2 electrons are
Present as one lone pair. thus, we have

i.e., it is a molecule of the type `AB_(3) L `. To minimise repulsions between lone pairs bond pairs, the shape
becomes pyramidal (non-planar).