Among the hydrides of chalcogens, which is most acidic and which is most stable ?

Among the hydrides of halogens Which is most acidic ?

Among the hydrides of halogens Which is most stable ?

Which hydride is most stable ?

Which hydride is most stable ?

Among the hydrides of group 15, which is (i) most basic (ii) most stable (iii) most volatile (iv) strogest reducing agent ?

Among the following alcohols, which one is most acidic?