Consider the following reactions:

PCl₃ + H₂O $$\to$$ A + HCl

A + H₂O $$\to$$ B + HCl

The number of ionisable protons present in the product B is _______________.

Consider the sulphides HgS, PbS, CuS, Sb₂S₃, As₂S₃ and CdS. Number of these sulphides soluble in 50% HNO₃ is ___________.

The number of halogen/(s) forming halic (V) acid is ___________.

A xenon compound 'A' upon partial hydrolysis gives XeO₂F₂. The number of lone pair of electrons present in compound A is _________. (Round off to the Nearest Integer)