Predict whether a precipitation reaction will occur when aqueous solutions of the following substances are mixed?
can someone please help i dont no how to tell if it will precipitate
MnCl_2 +Na_2S -----> 2NaCl + MnS(ppt)
2HNO_3 +CuSO_4-----> H2SO4 + Cu(NO3)2 (no ppt)
Substances which are insoluble are ppt
Salts of Na K and NH3 are always soluble so no ppt
All nitrates,bicarbonates,sulphates,chlorides are soluble
so all other substances like oxides and carbonates are insoluble
NOTE : ALL SALTS of NA K AND ammonia are soluble
REST ALL WILL FORM PPT's
To tell if there will be a precipitate, you need to look at the components of the two substances you are mixing, and then switch them to a different combination like this:
You start with Mn Cl and Na2S
Recombine the ions to get: Mn2S and NaCl. Remember to match up the positive and negatively charged ions, ie dont match up NaMn because they are both positively charged. The first ion listed will be positive, the second is negative
Now, check your solubility rules. If both of these new substances are soluble, you will NOT have a precipitate. So for this example, Mn2S would preciptate, because it is insoluble.
Here is a great list of solubility rules: http://www.ausetute.com.au/solrules.html
Looking at the rules for the sulfide ion, you see a list of cations (positive charge) with which it will be soluble (no precipitate), and it says that for all other cations it is insoluble. If it is insoluble, it will form a solid (precipitate from the solution). You can look at the same information for the Cl- anion, and you will see that NaCl would be soluble, so it would not precipitate.
A. SrSO4(s) + H2(g) + 2NO3(g) B. 2Na(NO3)(aq) + ZnSO4(s) C. No reaction D. NO reaction (they both remain aqueous)