According to collision theory of reactions, Why all molecular collisions do not result in effective collision?

According to collision theory of reactions, why all molecular collisions do not result in "effective collection"?

Which of the following is not conserved in inelastic collision ?

Which of the following is not conserved in inelastic collision ?

Use molecular orbital theory to explain why the Be_2 molecule does not exist.

A ball moving at 9m *s^(-1) , collides with an identical ball at rest. After collision, both the balls scatter at 30^@ with the initial direction of motion. Find the velocity of each ball after collision. Does the kinetic energy remain conserved in such a collision ?

According to the kinetic theory of gases, there are no intermolar attractions, so these molecules do not have

Assertion (A) : All collisions between the reactant molecules result in product formation . Reason (R) : The collision between molecules having sufficient amount of energy and proper orientations, results in the formation of compounds.

If the coefficient of restitution is zero for collision between two bodies then

If the coefficient of resittution is zero for collision between two bodies then