1 / 24

Solutions:

Solutions:. Homogeneous mixtures of two or more pure substances. The solvent is present in greatest abundance. All other substances are solutes. Dissociation. When an ionic substance dissolves in water, the solvent pulls the individual ions from the crystal and solvates them.

hang
Download Presentation

Solutions:

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. Solutions: • Homogeneous mixtures of two or more pure substances. • The solvent is present in greatest abundance. • All other substances are solutes.

  2. Dissociation • When an ionic substance dissolves in water, the solvent pulls the individual ions from the crystal and solvates them. • This process is called dissociation.

  3. Electrolytes • Substances that dissociate into ions when dissolved in water. • Anonelectrolyte may dissolve in water, but it does not dissociate into ions when it does so.

  4. Electrolytes and Nonelectrolytes Soluble ionic compounds tend to be electrolytes.

  5. Electrolytes and Nonelectrolytes Molecular compounds (covalently bonded) tend to be nonelectrolytes, except for acids and bases.

  6. Electrolytes • A strong electrolyte dissociates completely when dissolved in water. • A weak electrolyte only dissociates partially when dissolved in water.

  7. Strong Electrolytes Are… • Strong acids

  8. Strong Electrolytes Are… • Strong acids • Strong bases

  9. Strong Electrolytes Are… • Strong acids • Strong bases • Soluble ionic salts

  10. Table of Solubilities

  11. Solubility Rules for Ionic Salts • 1. Salts of ammonium (NH4+) and Group IA are always soluble. • 2. All halides (Cl-, Br- and I-) are soluble except AgCl, HgCl2, and PbCl2, which are insoluble. • 3. All Chlorates (ClO3-), nitrates (NO3-), and acetates (CH3COO-) are soluble.

  12. Solubility Rules Cont. • 4. Sulfates (SO42-) are soluble except CaSO4, SrSO4, BaSO4, Hg2SO4, HgSO4, PbSO4, and Ag2SO4 which are insoluble. • 5. Phosphates (PO43-), and carbonates (CO32-) are insoluble except NH4+ and Group IA compounds. • 6. All metallic oxides (O2-) are insoluble except NH4+ and Group IA compounds.

  13. Solubility Rules Cont. • 7. All metallic hydroxides (OH-) are insoluble except NH4+ and Group IA and Group IIA from Calcium down. • 8. All sulfides (S2-) are insoluble except NH4+ and Groups IA and IIA. • 9. All other Ionic compounds are assumed to be insoluble.

  14. Precipitation Reactions When one mixes ions that form compounds that are insoluble (as could be predicted by the solubility guidelines), a precipitate is formed.

  15. Metathesis comes from a Greek word that means “to transpose” AgNO3 (aq) + KCl (aq)  AgCl (s) + KNO3 (aq) Metathesis (Exchange) Reactions

  16. Metathesis comes from a Greek word that means “to transpose” It appears the ions in the reactant compounds exchange, or transpose, ions AgNO3 (aq) + KCl (aq)  AgCl (s) + KNO3 (aq) Metathesis (Exchange) Reactions

  17. Metathesis comes from a Greek word that means “to transpose” It appears the ions in the reactant compounds exchange, or transpose, ions Often known as “Replacement” reactions AgNO3 (aq) + KCl (aq)  AgCl (s) + KNO3 (aq) Metathesis (Exchange) Reactions

  18. Solution Chemistry • It is helpful to pay attention to exactly what species are present in a reaction mixture (i.e., solid, liquid, gas, aqueous solution). • If we are to understand reactivity, we must be aware of just what is changing during the course of a reaction.

  19. The molecular equation lists the reactants and products in their molecular form. AgNO3 (aq) + KCl(aq) AgCl(s) + KNO3 (aq) Molecular Equation

  20. In the ionic equation all strong electrolytes (strong acids, strong bases, and soluble ionic salts) are dissociated into their ions. This more accurately reflects the species that are found in the reaction mixture. Ag+(aq) + NO3- (aq) + K+ (aq) + Cl- (aq)  AgCl(s) + K+(aq) + NO3- (aq) Ionic Equation

  21. To form the net ionic equation, cross out anything that does not change from the left side of the equation to the right. Ag+(aq) + NO3-(aq) + K+(aq) + Cl-(aq) AgCl(s) + K+(aq) + NO3-(aq) Net Ionic Equation

  22. To form the net ionic equation, cross out anything that does not change from the left side of the equation to the right. The only things left in the equation are those things that change (i.e., react) during the course of the reaction. Ag+(aq) + Cl-(aq) AgCl(s) Net Ionic Equation

  23. To form the net ionic equation, cross out anything that does not change from the left side of the equation to the right. The only things left in the equation are those things that change (i.e., react) during the course of the reaction. Those things that didn’t change (and were deleted from the net ionic equation) are called spectator ions. Ag+(aq) + NO3-(aq) + K+(aq) + Cl-(aq) AgCl(s) + K+(aq) + NO3-(aq) Net Ionic Equation

  24. Writing Net Ionic Equations • Write a balanced molecular equation. • Dissociate all strong electrolytes. • Cross out anything that remains unchanged from the left side to the right side of the equation. • Write the net ionic equation with the species that remain.

More Related