According to the vsepr model, the progressive decrease in the bond angles in the series of molecules ch₄, nh₃, and h₂o is best accounted for by the

lone pair-bond pair repulsion is best accounted for decrease in bond angle

Explanation:

Bond angle in each compounds depends on presence of lone pair on central atom.

In , there is no lone pair on C atom. So, no lone pair-bond pair repulsion is present here. Hence is

In , there is one lone pair on N atom. So, one lone pair-bond pair repulsion is present here. Hence is

In , there are two lone pairs on O atom. So, two lone pair-bond pair repulsion are present here. Hence is

So, lone pair-bond pair repulsion is best accounted for decrease in bond angle

the molecules move in straight line until they collide with each other or with the walls of the container. collisions are perfectly elastic; when two molecules collide, they change their directions and kinetic energies, but the total kinetic energy is conserved.

explanation: