Reasonable Amount

There is no sin on you, if you divorce women while yet you have not touched (had sexual relation with) them, nor appointed unto them their Mahr (bridal - money given by the husband to his wife at the time of marriage). But bestow on them ( a suitable gift), the rich according to his means, and the poor according to his means, a gift of reasonable amount is a duty on the doers of good.

Al-Baqara [2:236]