Assume you are given an unknown aqueous solution that contains two or more of the six cations used in this experiment and the solution was tested with the cation classification cheme used in this experiment. Identify the cations present in the unknown solution based on the following observations that were made. Clearly state the reasons for your answer including your reasons for eliminating the cations you do not think are in the unknown solution. If the data are insufficient to definitively identify which cations are present, suggest an experiment or series of experiments that would allow you to accomplish this.

Observations made:

a$.$ The solution is blue$-$green in color.

b$.$ Addition of $6$ M NaCl to the solution produced a white precipitate.

c$.$ Addition of $6$ M NaOH to the original solution did not produce a gas $($red litmus

paper suspected over the solution stayed red$)$ but did produce a pale green precipitate.

d$.$ Addition of $6$ M NaOH to the solution from step b $($after the precipitate was removed$)$

produced a green precipitate.

e$.$ The entire precipitate from step d dissolved when $6$ M NH$3$ was added