Yes
dere is nothing like NH3OH it is always NH4OH
Yes, NH3 is a weak electrolyte.
Yes, ammonia NH3 is alkaline in solution (though weakly): NH3 + H2O <<--> NH4+ + OH-
NH3, or ammonia, is colorless, like water.
No. NH3 is a compound. An isotope is a variant of an element with a different number of neutrons. For example Carbon-12 and Carbon-14 are isotopes.