Which substance is reduced ?
Cl^2 +2KBr= 2KCl + Br2

Initially Br is in -1 oxidation state and Cl in 0 oxidation state. Finally Cl is in -1 o.s. and Br in 0.

This means that Br has oxidised from -1 to 0 and Cl is reduced from 0 to -1.

KBr is reducting agent as it helps Cl to reduce.

Cl2 is oxidising agent as it helps Br to oxidise.

Explanation:

intermolecular forces are the forces between molecules or particles.

there are two kinds of van der waals forces: weak london dispersion forces and stronger dipole-dipole forces.

in molecule of water there are dipole-dipole forces between negatively charged oxygen from one molecule of water and positively charger hydrogen of another molecule of water.

hydrogen bond is an electrostatic attraction between two polar groups that occurs when a hydrogen atom (h), covalently bound to a highly electronegative atom such as flourine (f), oxygen (o) and nitrogen (n) atoms.