posted by Sarah on .
Describe in detail the steps one would go through to make (in reality) 500mL of a 0.1M solution of cobalt(II) chloride from a container of powdered CoSO4.7H2O
You can't. There is no way you can weigh out CoSO4*7H2O and make it think it is CoCl2.
I was thinking maybe creating a chemical equation where a displacement reaction occurs... or maybe an equation with Cl ion being added?
2NaCl + CoSO4 --> Na2SO4 + CoCl2
Cl2 + CoSO4 --> CoCl2 + SO4
I just assumed you had made a typo. Apparently that is not the case. Let me think about it a couple of minutes and I'll get back to you.
What about adding BaCl2?
CoSO4.7H2O(aq) + BaCl2(aq) ==> CoCl2(aq) + BaSO4(s) + H2O
BaSO4 is a solid, it ppts (very insoluble), filter, wash thoroughly and all of the CoCl2 is in solution. Can you take it from here? As I see it, the CoSO4.7H2O can be weighed BEFORE starting the conversion, then collecting all of the CoCl2 and making to volume OR just take some CoSO4.7H2O, make the conversion, evaporate the CoCl2 soln to dryness, then weigh the correct amount of CoCl2 and go from there. I don't know the intent of the problem but as it's stated, I think you could go either way.