[THC]

I have to identify all the solutions. No chemicals are given, and all the solutions are 0.1 M.

I know the following:
The solutions are split into three groups. I know which solutions the groups consists of, but I don't know which one is which.
---
I: 1,2,3
a AgNO3
b BaCl2
c KI

II: 4,5,6,7
d CaCl2
e NaOH
f Na2SO4
g PbNO3

III: 8,9,10,11,12
h HNO3
i KNO3
j Na3PO4
k (NH4)2SO4
l Mg(NO3)2
---

Ok, so this is my suggestion. I would like you to correct it - and possibly find some easier solutions (no pun intended :-))

The table should be read like this:
Mixed together; outcome; solution, [outcome, solution etc.]
1+2 2+3 3+1: most yellow: c, no precipitate, b+c, last one: a
a+4,5,6,7: no precipitate: g
b+d,e,f: precipitate: f
f+d,e: no precipitate: e
last one: d
III: e+8,9,10,11,12:  precipitate: l, smell of ammonia: k
a+h,i,j: precipitate: j
e+k+h,i: most ammonia smelling: i
the other one: h

What do you think?

[Borek]

Looks good. Could be it looks good only on paper. I have failed similar test once because CaSO₄ didn't precipitate.

[AWK]

The table should be read like this:
Mixed together; outcome; solution, [outcome, solution etc.]
1+2 2+3 3+1: most yellow: c, no precipitate, b+c, last one: a

Assumed  your order
1+2 white
2+3 no reaction
3+1 pale yellow
You can identify all reagents within this group

Add AgNO3 , and separately KI to the samples of  II grup

Sometimes sulfates can precipitate Ag2SO4. If you cannot dilute samples with water (~5 times) then additional test is needed for solutions of II grup that gives white precipitates with AgNO3. Mix these solutions with BaCl2 - only BaSO4 precipitates (CaCl2 + BaCl2 - no reaction).

You can identify all reagents of the second group
Should be Pb(NO₃)²

III: e+8,9,10,11,12:  precipitate: l, smell of ammonia: k

OK
b+ 8,9,10 - precipitate j
a+e precipitate Ag2O which dissolves in HNO3 (h not i)

[THC]

The table should be read like this:
Mixed together; outcome; solution, [outcome, solution etc.]
1+2 2+3 3+1: most yellow: c, no precipitate, b+c, last one: a

Assumed  your order
1+2 white
2+3 no reaction
3+1 pale yellow
You can identify all reagents within this group

Yeah, I wasn't so clear about that. With "most yellow" I mean the precipitate with the most yellowish color.

Add AgNO3 , and separately KI to the samples of  II grup

Sometimes sulfates can precipitate Ag2SO4. If you cannot dilute samples with water (~5 times) then additional test is needed for solutions of II grup that gives white precipitates with AgNO3. Mix these solutions with BaCl2 - only BaSO4 precipitates (CaCl2 + BaCl2 - no reaction).

You can identify all reagents of the second group
Should be Pb(NO₃)²

I did not understand that part. I add AgNO2 to all in group II. All of them should precipitate except Pb(NO3)2, so I know how to identify Pb^2+ by that.

III: e+8,9,10,11,12:  precipitate: l, smell of ammonia: k

OK
b+ 8,9,10 - precipitate j
a+e precipitate Ag2O which dissolves in HNO3 (h not i)

So I should use Ba^2+ instead of Ag+? Why is that?
Wouldn't my last test for  KNO3/HNO3 work, and why not? ("the other one" should be h, not i, of course. Edited in my original post):

e+k+h,i: most ammonia smelling: i
the other one: h

[AWK]

Yeah, I wasn't so clear about that. With "most yellow" I mean the precipitate with the most yellowish color.

as "most yellow: I understand there are other yellop przecipitates in this group, but there is only pure white one.

I did not understand that part. I add AgNO2 to all in group II. All of them should precipitate except Pb(NO3)2, so I know how to identify Pb^2+ by that.

AgNO3 ?

Ag2SO4 is sparingly soluble in water. Depending on concentration of both solution and temperature (I mean RT from Alaska to Los Angeles) yoy can obtain precipitate or not.

I do not understand this one

e+k+h,i: most ammonia smelling: i

do you mean:
e+k,h,i

In my opinion you did not differentiate h and i - the only method is checking which one is an acid (solubilize Ag2O or Ag3PO4

[THC]

Ag2SO4 is sparingly soluble in water. Depending on concentration of both solution and temperature (I mean RT from Alaska to Los Angeles) yoy can obtain precipitate or not.

Thanks, I did not know that. I just looked at a solubility table.

I do not understand this one

e+k+h,i: most ammonia smelling: i

do you mean:
e+k,h,i

In my opinion you did not differentiate h and i - the only method is checking which one is an acid (solubilize Ag2O or Ag3PO4

No, I mean e+k and then h and i. e+k - or NaOH + (NH4)2SO4 - yields NH3. If HNO3 is added to the soultion, NH4+ is formed. If KNO3 is added, nothing happens and the solution stinks of ammonia
I don't know if it'll work. It does require some relatively precise measurements, and we will only use those plastic pipettes, I think.