Make dissapear a object after passing some seconds

Hi,
I have done a prefab bullet, I use it to make my character shoots against enemies, when it collide with an enemy it hurts it and an explosion occour, but I notified that if it doesn’t collide with the enemy the bullet remains on a unkown part of the scene.
Can you say me if there is any function to destroy the object passing some seconds?
Lot of thanks

var lifeTime = 5.0;

function Awake ()
{
Destroy(gameObject, lifeTime);
}

I believe that is how it is done. Put this on your bullet and it should work.