Acids and Bases Arrhenius Acids and Bases Arrhenius

Acids and Bases

Arrhenius Acids and Bases • Arrhenius acid: Break apart (dissociate) to yield hydrogen ions (H+) in water (aqueous) solutions HCl → H+ + Cl • Arrhenius base: Break apart (dissociate) to yield hydroxide ions (OH-) in water (aqueous) solutions Na. OH → Na+ + OH-

Naming Acids and Bases Acids: Remember this chart? ? ? Anion Ending Acid Name -ide hydro-(stem)-ic acid -ite (stem)-ous acid -ate (stem)-ic acid Bases: cation name + hydroxide

The p. H Scale

The p. H scale Acidic solution: Neutral solution: Basic solution: ACIDIC Neutral p. H < 7. 0 p. H = 7. 0 p. H > 7. 0 BASIC p. H = Increasing acidity Increasing basicity

p. H (“potential hydrogen”): a way of expressing the hydrogen ion concentration p. H = - log [H+] = the hydrogen ion concentration IN MOLARITY [H+] = 10 -p. H

The p. H Scale - As p. H increases, [H+] decreases - As p. H decreases, [H+] increases

Calculating p. H [H+] = 10 -p. H Acidic Solution p. H < 7. 0 [H+] > 1 x 10 -7 Neutral Solution p. H = 7. 0 [H+] = 1 x 10 -7 Basic Solution p. H > 7. 0 [H+] < 1 x 10 -7

Just like p. H… p. OH (“potential hydroxide”): a way of expressing the hydroxide ion concentration p. OH = - log [OH-] = the hydroxide ion concentration IN MOLARITY Just like [H+]: [OH-] = 10 -p. OH p. H + p. OH = 14

Bronsted-Lowry Acids and Bases • Bronsted-Lowry acid: donates a proton (H+) in solutions • Bronsted-Lowry base: accepts a proton (H+) in solutions HNO 2 + H 2 O ↔ NO 2 - + H 3 O+ B-L acid B-L base

Conjugate Acids and Bases • Used in Bronsted-Lowry definition ONLY • Conjugate acid: the acid formed when a proton (H+) is added to the base • Conjugate base: the base formed when a proton (H+) is removed from the acid HNO 2 + H 2 O ↔ NO 2 - + H 3 O+ B-L acid B-L base Conjugate acid