Question

a. Would you except the hydrides of `N,O` and `F` to have lower boiling points than the hydrides of their subsequent group members? Give reason.
b. Can phosphorous with outer electronic configuration `3s^(2)3p^(3)` form `PH_(5)`?
c. How many hydrogen-bonded water molecules(s) are associated with `CuSO_(4).5H_(2)O`?

Answer 1

Although phosphorus exhibits +3 and +5 oxidation states, it cannot form PH5. Besides some other considerations, high `Delta_(a)H` value of dihydrogen and `Delta_(eg)H` value of hydrogen do not favour to exhibit the highest oxidation state of P, and consequently the formation of `PH_(5)`.