SELF-IONIZATION OF WATER A. To understand whether a solution is an acid or a base, we’ll use pure water as a __________ starting point. NEUTRAL

SELF-IONIZATION OF WATER B. Although pure water is mostly molecules of H2O, conductivity measurements indicate a small amount of ______ are present from the _________________ of small amounts of the water molecules. ions SELF-IONIZATION

SELF-IONIZATION OF WATER 1. In the self-ionization of water, two water molecules produce a hydronium ion. H3O+, and a hydroxide ion, OH-.

SELF-IONIZATION OF WATER 2. The self-ionization of water produces _______ amounts of hydrogen and hydroxide ions at a concentration of __________ each (at 25°C). Because these ions are in equal concentrations, we say that pure water is __________. EQUAL 1.0X10-7M NEUTRAL

SELF-IONIZATION OF WATER C. The equilibrium constant, Kw, for the self-ionization of water at 25oC is, therefore, equal________. 1x10-14

SELF-IONIZATION OF WATER Kw = [H1+] [OH1-] Kw = (1.0x10-7M) (1.0x10-7M) Kw = __________ 1.0X10-14

SELF-IONIZATION OF WATER 1. Notice that the equilibrium constant expression, Kw, does NOT include [REACTANTS], because the reactant is ______. liquid

SELF-IONIZATION OF WATER 2. REMEMBER that a K value that is less than 1 indicates there is a LOT of _________ present at equilibrium. In other words, water is mostly water molecules and there is very little H3O+ or OH-. Reactants

SELF-IONIZATION OF WATER 3. Recognize that the reaction for the self-ionization of water is _____________ (energy is put in to break the bonds of the water molecules), and like other reactions, the Kw value will be affected by temperature endothermic