Is it permissible for a mother to account for an increase in her apartment's rent from her Zakat money, knowing that her tenants are poor students and she fears burdening them by raising the rent?

It is not permissible for the mother to raise the rent on the students if there is a fixed-term contract. An increase is permissible after the contract period ends. However, deducting the increase and considering it from the zakat is not permissible, because that benefits the mother. Zakat can be given to the poor and they can be given ownership of it, so they may dispose of it to pay rent or meet their other needs.