[sinjid9]

Also another solubility related question.
The waste water dumped into a river from plant A contains dissolved magnesium sulphide. A second plant, Plant B's waste water contains strontium hydroxide in solution. A third plant, plant C, has some silver sulphate dissolved in the water it discards into the river. When these waste waters eventually mix, various precipitates form.
a. Write balanced equations to identify all of the precipitates which form and are deposited as sludge on the river bottom.

I wrote:
MgS(aq) + Sr(OH)2(aq) -> SrS(aq) + Mg(OH)2(s)         (Didn't get an x or a checkmark. I don't think he saw it I drew it somewhere at the top of the page)


Ag2(SO4)(aq) + MgS(aq) -> Ag2S(s) + Mg(SO4)(aq)        (Got mark)

Ag2(SO4)(aq) + Sr(OH)2 -> 2Ag(OH)(s) + Sr(SO4)(s)     (Got mark)

SrS(aq) + Ag2(SO4)(aq) -> Sr(SO4)(s) + Ag2S(s)  (Got ?? written on the SrS(aq))


MgSO4(aq) + Sr(OH)2(aq) -> Mg(OH)2 + Sr(SO4)(s)  (Got ?? written on the MgSO4(aq))

Borek I understand your last post, but for this one, I am unable to choose the elements myself.
Anyone know whats wrong with the last 2?