If you struck the 8 ball first as a legal shot, and the cue ball or eight ball pockets the opponents ball, this is not loss of game under league play and typical local rules, regardless of whether the 8 ball goes in or not.
However, under some local rules, if you failed to call this as a part of your shot, it is may not be allowed, resulting in either spotting the 8 ball or loss of game.
As soon as you hit your opponents ball it is a foul. Under most rules, this results in ball in hand. However, under other rules, knocking the 8 ball in when it is not the object ball is loss of game.
Yes. If your object ball is the black 8 ball and it is not the ball that is hit first, it is a foul.
No. The first ball contacted by the cue ball must be the 8 ball to be a legal shot. However, if you use the opponent's ball as a carom shot after hitting the 8 ball, yes, this is a legal shot.
you loose your turn and your opponent gets to use the q ball to his adventage
you have to break it and make the 8 ball go in a pocket (at the same time)
If the cue ball goes in it is a foul - the pocketed ball may or may not be removed and spotted depending upon the ball and rules of play. In the game of 8 ball, if the other ball is the 8 ball it is loss of game.
you get a 9
If you're referring to a foul, it's ball in hand for the incoming player, provided it is a cue ball foul (i.e. scratch, ball off table, hitting opponents ball before your own, etc.). I believe some fouls result in loss of turn, but not ball in hand (i.e. - an object ball leaves the table).
500
This depends on the specific rules of the game you play. Under BCA and APA Rules the other player gets ball-in-hand.
Under normal rules, you must contact the 8 ball in a legal shot as the first ball hit and any bal must contact a rail or the 8 ball must go in a pocket.
there is no 8 ball