1 / 14

Predicting solubility

Predicting solubility. Using the table of solubilities we can now predict which of the products of a double replacement reaction will be insoluble ( form solids or precipitates : have low solubilities) and which will remain soluble. Pb(NO 3 ) 2 (aq) + 2 KI(aq)  PbI 2 (s) + 2KNO 3 (aq).

conan-fitzgerald
Download Presentation

Predicting solubility

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Predicting solubility

  2. Using the table of solubilities we can now predict which of the products of a double replacement reaction will be insoluble (form solids or precipitates : have low solubilities) and which will remain soluble.

  3. Pb(NO3)2(aq) + 2 KI(aq)  PbI2 (s) + 2KNO3(aq) • overall ionic equation, which separates all the ions out: Pb2+(aq) + 2 NO3- (aq) + 2 K- (aq) + 2 I- (aq)  PbI2 (s) + 2 K+ (aq) + 2 NO3- (aq) Pb2+ (aq) + 2 I- (aq)  PbI2 (s) Stays as a solid

  4. The NO3- ion and the K+ ion are called spectator ions.

  5. Silver nitrate combines with potassium iodide. • a) Nonionic or double replacement reaction AgNO3 (aq)+KI (aq) → AgI (?)+KNO3 (?)

  6. Using the solubility table we see that nitrates are soluble with all positive ions and Iodide ion is insoluble with silver. AgNO3 (aq)+KI (aq)→AgI (s)+KNO3 (aq)

  7. Now that we have predicted the solid that will form we can proceed to write the net ionic equation. • Ag + (aq) + I- (aq) → AgI (s)

  8. silver nitrate + potassium iodide • ammonium sulfide + lead(II) nitrate • zinc nitrate + sodium carbonate

  9. Separating ions:Pb 2+ (aq) ; Ba 2+ (aq) ; Cu 2+ (aq) Add Cl- Ba2+ and Cu2+ soluble PbCl2 ppt outs Add S2- Add PO43- CuS ppt out Ba2+ soluble Ba3 (PO4)2 ppt out

  10. Using the solubility table create a flow chart that describes how to separate the following ions, if they are dissolved together in a solution. The last ion may remain in solution. • a) Ag+ (aq) ; Ba2+ (aq) ; Mg2+ (aq) • b) Ba2+ (aq) ; K+ (aq) ; Zn2+ (aq) • c) Pb2+ (aq) ; Al3+ (aq) ; Sr2+ (aq) • d) Sr2+ (aq) ; Mg2+ (aq) ; Fe3+ (aq)

  11. 1. Ionic Substances ( containing a metal or NH4- ion ) • Ionic substances are composed of positive and negative ions. Arrhenius proposed that ionic substances come apart when they enter a water solution, and the ions are free to move about in the solution. The called this process dissociation. • CaCl2 (s) -------> Ca 2+ (aq) + 2 Cl- (aq) • * Notice that the reactions are balanced for charge and # of atoms.

  12. 2. Acids (containing nonmetals with hydrogen written first in the formula) • Certain molecular substances also form mobile ions when placed in solution. Arrhenius proposed that acids when placed in solution form mobile ions. He called this process ionization. • H2 SO4 (l) -------> 2 H+ (aq) + SO4 2- (aq) • In both cases (dissociation and ionization) the end result is mobile ions in solution. Thus since ions are present and can move, both acids and ionic substances conduct electricity in solution and are termed electrolytes.

  13. 3. Molecular (contain only nonmetals) • Molecular substance that are not acids on the other hand do not ionize nor dissociation and do not form ions in solution. Therefore these substances are non-electrolytes. • CO2 (g) ------> CO2 (aq)

More Related