Is it permissible to pay Zakat on money to a brother who lives in a rented apartment and wishes to buy an apartment, knowing that he works in the private sector? And is Zakat due on a wife's jewelry?

It is permissible to give zakat to a poor or needy brother; in fact, it is more meritorious, as it is both charity (sadaqah) and an act of kinship (silah). As for a wife's jewelry, if it is prepared for use, there is no zakat on it according to the majority of scholars, but giving zakat on it is more precautionary to avoid disagreement. However, if it is not prepared for use, then zakat is obligatory on it.