Is money donated for the sponsorship of an orphan and for hospitals considered sadaqah (charity) or zakat, given the donor's intention to seek Allah's pleasure, and the obligation of zakat upon him?

The intention for Zakat is a prerequisite when disbursing it. If one does not intend it as Zakat at the time of giving the money, it is not valid, and thus the obligatory amount of Zakat must be given. Zakat may be given to a poor orphan and for the treatment of a poor patient. However, the majority of scholars prohibit giving it for the construction of a hospital.