Momentum vs Impulse
Momentum is a property of a moving body and describes the force that is required to stop a moving body. When we say that a particular team has momentum at the moment, we mean to say that the team is on a roll and hard to be stopped by other teams in the tournament. Any object having momentum needs a force against it, and this force also needs to be applied for some time to stop the body. More the momentum, harder is it to stop a body. So it is clear that a moving body with a momentum can be stopped if a particular force is applied against it for some time.
According to Newton’s 2nd law of motion, Force is the product of mass and the acceleration of a body. Now acceleration is rate of change of velocity, so we can say that
F = m X a
= m X v1 v2/t = m(v_{1} v_{2)/t}
In this equation, if we multiply both sides by t, we get new equation as F X t = m X (v_{1} v_{2)}; F. t = m(v_{1} v_{2)}
On the right side of the equation is change in momentum of the body, and on the left side is an important property of the body known as Impulse.
Thus Impulse = change in momentum
Impulse is an important concept in the study of collisions and the above equation is an important one known as impulsemomentum change equation. When we talk about impulse, we are really talking about change in momentum of a moving body, and the rate of change in momentum is the force applied upon the body.
In brief: Momentum vs Impulse • Since impulse is only change in momentum, it has same units as that of momentum which is kg m/s • Impulse is also defined as force acting for duration upon a body • Momentum of a moving body is the product of its mass and its velocity whereas impulse is change in momentum which is the product of mass and difference in velocities.

Related Links:
1. Difference Between Impulse and Force
2. Difference Between Momentum and Energy