Is the prayer of one who performed ablution and then passed gas accepted if he is unsure whether he invalidated his ablution or not, and he prayed while in a state of impurity?

If your feeling of passing wind is merely a doubt, do not pay attention to it, and continue with your worship, for it is valid. This is from the whispers of Satan. However, if you have certain conviction that wind has passed, to the extent that you could swear by it, then you must perform ablution again. If you suffer from incontinence, perform ablution after the time for prayer has begun and pray your obligatory prayers and as many supererogatory prayers as you wish with that ablution. Beware of abandoning prayer, for it is a grave sin.