#1-yes. The strong acids transpose all phosphates, incl your K acid phosphate. and if you boil the H20 away and heat more the reaction reverses, except the sulfate gives SO3, and the heat converts the HXPOX- to other phosphates.
#2-no. KH2PO4+NH4OH+H2O=KNH4HPO4. your orthophosphate is an acid even as a salt, so it probably reacts as shown giving the double salt, or maybe not, solubilities of the reactants and products could influence this one. but this is a great place to start your chemistry- nothing will blow up-just b careful w/the acid. just do it and see what happens! you can test for orthophosphate(H2PO4-) ion by adding MgSO4(aq),NH4Cl, and NH4OH to it. you should get a precipitate of MgNH4PO4. don't ask-READ, DO, and B SAFE!
could it bee someone looking into my mind
from some other place at some other time?