this is the second general unknown in lab.
my prof. told me i can have 1 or cations and 1 or 2 anions.
The Attempt at a Solution
cation analysis: i carried out blanket tests by adding na2co3, naoh, and nh4oh to my salt dissolved in water to three different test tubes to see if a precipitate formed. a precipitate formed for all three (so i am not able to eliminate any cations from these blanket tests)
anion analysis: i added agno3 to the salt solution and a white precipitate formed, which says that br-, i-, s2-, po43-, cro42- are absent. i then tried to dissolve the ppt with hno3 and it did not dissolve and according to the test it says i have (cl-, br-, i-, and s2-)
one last note: i get a green solution when i mix my unknown salt with water, and my text says this: "Suppose a salt mixture dissolves readily and completely in cold water to give a green solutiom. A green solution means the presence of copper, nickel, iron (II), or chromium. the mixture cannot, therefore, contain carbonates, sulfites, phosphates, borates, chromates, or sulfides.
i tried to test for group 3 cations (fe, co, ni, mn, al, cr, and zn) but i didn't get anything (but i also think i could have made a procedural error)
any guess at what i may have????? thank you