Acids and Bases

Properties of Acids  A dilute acid tastes sour.  When a reactive metal is added to an acid it produces H2(aq)  When an acid is tested with Litmus paper, the paper turns red.  When phenolphthalein is added to an acid, no reaction occurs.  Acids are electrolytes.  When an acid and a base are added together the products are water and salt.

Properties of Bases  A dilute base tastes bitter.  If a metal oxide and water are combined a base is formed.  When a base is tested with Litmus paper, the paper turns blue.  When phenolphthalein is added to a base, the base turns pink.  Bases are electrolytes.  When an acid and a base are added together the products are water and salt.

Arrhenius Acid An acid is anything that releases H+ in solution. Example: HCl(aq)  H+(aq) + Cl-(aq) HBr, HF, HI, H2SO4, HNO3, H3PO4, H2CO3, CH3COOH

A base is anything that releases OH- in solution. Arrhenius Bases A base is anything that releases OH- in solution. Example: NaOH(aq)  Na+(aq) + OH-(aq) NaOH, KOH, LiOH, Sr(OH)2

Neutralization  occurs when in acid-base reactions equal quantities of an acid and base are mixed.  the products are salt and water  the products are neither acid nor base which makes them neutral Example: HCl + NaOH  NaCl + H2O

Titration Titration is the process of metering a standard solution into a solution of unknown concentration. Formula: MA x VA = MB x VB If 50.0mL of 1M KOH is used, how much 2M HCl is needed to titrate this reaction? 2M x X = 1M x 50.0mL X = 25.0mL

A Bronsted-Lowry base is anything that accepts a proton. Bronsted-Lowry Acid A Bronsted-Lowry acid is anything that donates a proton. Bronsted-Lowry Base A Bronsted-Lowry base is anything that accepts a proton.

Examples HCl + NH3 --> NH4+ + Cl- Acid Base Acid Base HCl + H2O --> H3O+ + Cl- Acid Base Acid Base NH3 + H2O --> NH4+ + OH- Base Acid Acid Base Water can either be an acid or a base. Water is therefore an amphoteric substance.

Conjugate Acid-Base pairs Conjugate acid-base pair: in an acid-base reaction, an acid transfers a proton to become a conjugate base, this acid and the newly formed base form an acid-base pair. Example: HCl + NH3 --> NH4+ + Cl- Acid Base Acid Base HCl and Cl- are an acid-base pair and NH3 and NH4+ are an acid-base pair in this equation.

pH H2O + H2O --> H3O+ + OH- Kw = [H3O+][OH-] Kw = 1 x 10-14 pH = -log[H3O+] 7 = -log[1 x 10-7] HCl + H2O  H3O+ + Cl- 1 x 10-3M 1 x 10-3M pH = 3 NaOH  Na+ + OH- .01M 1 x 10-2 pH = 12

Strong Acids Strong Bases HI HBr HCl HNO3 H2SO4 HClO4 LiOH NaOH KOH RbOH CsOH

Hydrolysis Hydrolysis is a process by which some salts react with water to form solutions that are acidic or basic. Examples: NaCl + H2O  HCl + NaOH Neutral NaF + H2O  HF + NaOH Basic MgCl2 + H2O  HCl + Mg(OH)2 Acidic

THE END