U5 Acids and Bases Honors Chemistry PDF

U5, part 2: Acids, and Bases Introduction to acids and bases 1) list and describe the physical and chemical properties of acids and bases 2) explain the formation of the hydronium ion 3) classify acids and bases according to the Arrhenius, Bronsted-Lowry, and Lewis models Strength and co...

U5, part 2: Acids, and Bases Introduction to acids and bases 1) list and describe the physical and chemical properties of acids and bases 2) explain the formation of the hydronium ion 3) classify acids and bases according to the Arrhenius, Bronsted-Lowry, and Lewis models Strength and concentration 4) distinguish between the strength and concentration of acids and bases (strong/weak; concentrated/diluted); distinguish between monoprotic, diprotic, and polyprotic acids pH 5) distinguish between pH vs. pOH; solve pH problems Neutralization 6) describe neutralization reactions 7) solve titration problems Introduction to acids and bases ACIDS BASES Taste sour bitter Change the color of blue litmus to red, red litmus to blue, indicators bromothymol blue to yellow phenolphthalein to fuschia Neutralization neutralize bases neutralize acids Electric conductivity strong acids are good strong bases are good conductors conductors Danger to organic corrosive caustic tissue Feel astringent slippery Differences between acids and bases video  The usual solvent for acids and bases is water—water produces equal numbers of hydrogen and hydroxide ions in a process called self-ionization. H2O(l) + H2O(l) H3O+(aq) + OH–(aq) The hydronium ion is H3O+. Copyright © McGraw-Hill Education Introduction to Acids and Bases The Arrhenius Model, 1883 An acid is a substance that contains hydrogen and ionizes to produce hydrogen ions in aqueous solution, and a base is a substance that contains a hydroxide group and dissociates to produce a hydroxide ion in solution. Arrhenius acids and bases: – HCl ionizes to release H+ ions. HCl(g) → H+(aq) + Cl–(aq) – NaOH dissociates to release OH– ions. NaOH(s) → Na+(aq) + OH–(aq) Svante Arrhenius 1859 - 1927 (aged 68) Swedish Physical Institute of the Swedish Academy of Sciences Copyright © McGraw-Hill Education Introduction to Acids and Bases The Brønsted-Lowry Model, 1923 An acid is a proton (H+) donor, and a base is a proton (H+) acceptor. A conjugate acid is the species produced when a base accepts a proton (H+) A conjugate base is the species produced when an acid donates a proton (H+) A conjugate acid-base pair consists of two substances related to each other by donating Johannes Brønsted and accepting a single proton (H+) 1879 - 1947 (aged 68) Danish Ph.D. from the University of Copenhagen Thomas Lowry simultaneously 1874 - 1936 (aged 62) British and independently Degree from Technical College... Copyright © McGraw-Hill Education Introduction to Acids and Bases The Brønsted-Lowry Model Brønsted-Lowry acids – HF(aq) + H2O(l) H3O+(aq) + F–(aq) – HF = acid, H2O = base, H3O+ = conjugate acid, F– = conjugate base Brønsted-Lowry bases – NH3(aq) + H2O(l) ↔ NH4+(aq) + OH–(aq) – NH3 = base, H2O(l) = acid, NH4+ = conjugate acid, OH– = conjugate base Water and other substances that can act as acids or bases are called amphoteric. Copyright © McGraw-Hill Education Introduction to Acids and Bases The Lewis Model,1923 A Lewis acid accepts a pair of nonbonding electrons and a Lewis base donates a pair of nonbonding electrons Gilbert Lewis 1875 - 1946 (aged 70) American PhD in chemistry from Harvard University Copyright © McGraw-Hill Education Introduction to Acids and Bases Examples of Lewis acids and bases Notice the curved arrows, they show the transfer of the non-bonding (LONE) pair of electrons (FROM THE BASE TO THE ACID)  You try now… 1) give the name of each species 2) draw an curved arrow to show the donated non-bonding electrons 3) identify the Lewis acid and the Lewis base Strength and concentration Concentration (section 16.9 of your textbook) M = moles of solute / liters of solution Practice: A solution is prepared by dissolving 42.23 g of HCl(g) into enough water to make 500.0 mL of solution. Calculate its molarity Strengths of Acids… NOT the same as concentration STRONG acids WEAK acids degree of 100%