A solution contains some or all of the ions Cu2 , Al3 , K , Ca2 , Ba2 , Pb2 , and NH4. The following tests were performed, in order, on the solution. Addition of 6 M HCl produced no reaction. Addition of H2S with 0.2 M HCl produced a black solid. Addition of (NH4)2S produced a white solid. Addition of (NH4)2HPO4 in NH3 produced no reaction. The final supernatant when heated produced a purple flame. Identify which of these ions were present in the solution, which were absent, and for which ones no conclusions can be drawn.
bins are: present. absent. and Inclusive.
options: K+ Ba2+ NH4+ Al3+ Pb2+ Ca2+ Cu2+

more info ? ? i don't understand what the question is

explanation:

the correct answer is b. a strong acid completely dissociates to its ions when dissolved in water. completely dissociates to and ions. a is incorrect because does not fully ionize to and ions and some remain as the compound . c and d are incorrect because, and do not fall into the category of bronsted lowry acids. a bronsted lowry acid is a proton donor and since both molecules do not have a proton to donate they are not bronsted lowry acids. likewise,   if we use the lewis acid definition, they cannot be acids. a lewis acid is an electron pair acceptor. both and have a complete octet so can not accept any electrons which disqualifies them as acids.