Using the solubility chart below, identify the cations that would be expected to form a precipitate upon initial addition of sulfate (i.e. SO4 2- OR S O4 2 minus)
Solubility Table
Header Row
Ion Solubility Exceptions
Table Body arranged in rows
N O 3 minus soluble none
C l minus soluble except A g+, H g2 2+, *Pb2+
I minus soluble except A g+, H g2 2+, *Pb2+
S O4 2minus soluble except C a 2+, B a2+, S r2+, H g2+, P b2+, A g+
C O3 2minus insoluble except Group IA and NH4+
P O 4 3 minus insoluble except Group IA and NH4+
O H minus insoluble except Group IA, *C a 2+, B a 2+, S r 2+
S 2 minus insoluble except Group IA, IIA and NH4 1+
N a+ soluble none
K+ soluble none
NH4 1+ soluble none
*= partially soluble
End Table
- Pb2+
- C a 2+
- A g+
- B a 2+
Using the table below from http://www.docbrown.info/page07/appendixtrans12.htm
match the cations with the color of the precipitate that it will form INITIALLY when treated with hydroxide. NOTE : More than one might have the same color.
- Ni2+
- Al3+
- Cr3+
- Fe3+
- Cu2+
- Zn2+
1. green gel
2. brown gel
3. blue gel
4. white gel
__1__ Ni2+
__4__ Al3+
__1__ Cr3+
__2__ Fe3+
__3__ Cu2+
__4__ Zn2+