Anhydrous `CaCl_(2),P_(4)O_(10)` or concentrated `H_(2)SO_(4)` can not be used as drying agent for ammonia.Why ?

Explanation

Ammonia cannot be dried using `CaCl_(2), P_(2) O_(5)` or concentrated `H_(2)SO_(4)` because `NH_(3)` reacts with all of these.
`{:(CaCl_(2) + 8NH_(3) rarr CaCl_(2).8NH_(3),P_(2)O_(5) + 6NH_(3) + 3H_(2)O rarr 2(NH_(4))_(3) PO_(4)),(H_(2) SO_(4) + 2NH_(3) rarr (NH_(4))_(2) SO_(4),CaO + H_(2)O rarr Ca(OH)_(2)):}`