1 / 6

Acid/Base Strength

Acid/Base Strength. Strong and Weak Acids. Strong acids : completely ionize in aqueous solutions HCl (g) + H 2 O (l)  H 3 O + (aq) + Cl - (aq) Weak acids : ionize slightly ion aqueous solutions CH 3 COOH (aq) + H 2 O (l) H 3 O + (aq) + CH 3 COO - (aq)

abra
Download Presentation

Acid/Base Strength

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. Acid/Base Strength

  2. Strong and Weak Acids • Strong acids: completely ionize in aqueous solutions HCl (g) + H2O (l) H3O+(aq) + Cl-(aq) • Weak acids: ionize slightly ion aqueous solutions CH3COOH (aq) + H2O (l) H3O+(aq) + CH3COO-(aq) • Table on pg. 645 gives formulas for common weak acids

  3. Strong and Weak Acids • Another clue: the conjugate base! • Strong acids have WEAK conjugate bases • Weak acids have STRONG conjugate bases HCl (g) + H2O (l) H3O+(aq) + Cl-(aq) weak c.b. CH3COOH (aq) + H2O (l) H3O+(aq) + CH3COO-(aq) strong c.b.

  4. Acid Dissociation Constant (Ka) • For weak acids: Ka = [H3O+]coeff. x [A-]coeff. [HA]coeff. • Weak acids have small Ka values, strong acids have larger Kavalues. CH3COOH(l) + H2O(l) CH3COO-(aq) + H3O+(aq)

  5. Strong and Weak Bases • Strong bases: dissociate completely into metal ions and hydroxide ions in water NaOH (s) Na+(aq) + OH-(aq) • Weak bases: react with water to form a hydroxide ion and the conjugate acid of the base. NH3 (aq) + H2O (l) NH4+(aq) + OH-(aq)

  6. Base Dissociation Constant (Kb) • For dilute (weak) bases: Kb = [conjugate acid]coeff. x [OH-]coeff. [base]coeff. NH3 (aq) + H2O (l) NH4+(aq) + OH-(aq) • Weak bases have small Kb

More Related