11-6-08[lecture18]tc

11-6-08[lecture18]tc - Lecture 18 (TC) Nov. 6, 2008 Notes...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Lecture 18 (TC) Nov. 6, 2008 Notes Arrhenius Acids/Bases: ‐ Arrhenius Acids have a removable H+. ‐ Arrhenius Bases have a removable OH‐. ‐ Arrhenius acid‐base RXNs have the format/model: 1) Acid + Base →← Salt + Water > HA + B(OH) →← (B+)(A‐) + H2O 2) HA →← H+ + A‐ B(OH) →← B+ + OH‐ = HA + B(OH) →← H+ + A‐ + B+ + OH‐ Bronsted‐Lowry Acids/Bases: ‐ Bronsted‐Lowry Acids have removable H+. ‐ Bronsted‐Lowry Bases can ‘accept’ H+ from an acid (acid 1 or acid 2). ‐ Removing H+ causes the corresponding base to be more ‘negative’ charge. ‐ Conjugates: Related by H+. ‐ Bronsted‐Lowry Acid/Base RXNs usually have the format: 1) Acid 1 →← H+ + Base 1 Base 2 + H+ →← Acid 2 = Acid 1 + Base 2 + H+ →← H+ + Acid 2 + Base 1 > ‘H+’ gets crossed out on both sides (like intermediates). = Acid 1 + Base 2 →← Acid 2 + Base 1 (or) = HA + B →← HB+ + A‐ Arrhenius: ‐ Arrhenius Acids produce H+ when added to water ((l) H2O). ‐ Arrhenius Bases produce OH‐ when added to water ((l) H2O). Bronsted‐Lowry: ‐ Bronsted‐Lowry Acids donate protons (H+). ‐ Bronsted‐Lowry Bases accept protons (H+). Amphiprotic Substances: ‐ Some chemicals can be an acid or a base. ‐ Water is an Amphiprotic Substance. ‐ Water can be both a proton donator as well as a proton acceptor. ‐ Autoionization: a fast equilibrium rxn that is always occurring whenever there is water present. Using the table of Conjugate Acid‐Base Pairs: ‐ The acids column is in order from Large to Lowest Ka. (Top to bottom order). ‐ The Base column is in order from weakest to strongest. (Top to bottom order). ‐ The stronger the acid, the weaker the base. ‐ The weaker the acid, the stronger the base. Conjugate: ‐ Conjugate acids/bases differ by a H+. Acid Ionization constant: K a ‐ Acid ionization constant = ‐ This is a measure of ACID STRENGTH. ‐ If Ka is larger, the Acid is stronger. If its smaller, the Acid is weaker. ...
View Full Document

Ask a homework question - tutors are online