Weak Acids, Weak Bases, and Salts

It completely dissociates into ions

concentration of hydronium ions is equal to the concentration of the strong acid; or the concentration of hydroxide ions is equal to the concentration of the strong base

Involves the concentration of hydronium ions and are expressed on the logarithmic scale of pH: pH= -log[H3O+]

By the ion product of water Kw which has a value of: Kw= [H3O+][OH-]= 1.0 x 10^-14

-log[OH]-

-log[H3O+]-log [OH-] = +14.00 so Pkw = pH + pOH = 14 and now if one of these is known the other three may be calculated using the previous three formulas

they do not dissociate completely; react with water to ionize only partly and try to reach a state of equilibrium

dissociation or ionisation constants which have a definite value at a specific temperature, depending on whether the reactant is a base or acid they are called acid ionization constants and base ionization constants, respectively

they dissociate completely into their ions but the fate of these ions depends on the acid or base from which they are derived

they are simply hydrated- surrounded by water molecules

they react with water in a process called hydrolysis

the process in which anions and cations of weak acids and bases reacts with water

the pH and concentration of a salt

Obtain 200 mL of distilled water and boil to remove CO2; Rinse test tubes and rinse with 2mL of solution to be tested then add 5mL of solution into each test tube; add 3 or 4 drops of indicators to test tube, record color

pH paper has indicator and two types of readings are produced, wide-range and short range; wide range covers nearly whole scale,e short range covers colors within a certain range; test pH of a solution using wide-range then use short range to obtain a more exact pH; boil off CO2 from distilled water; gently arrange pH paper and clean a stirring rod and touch wet stirring rod with solution to wide range pH paper than use the appropriate short-range pH paper once it is determined which range it approximately falls into

set temperatur ecompensation dial to temperature of solution; immerse electrodes in liquid; calibrate meter with buffer solutions; rinse electrodes with Co2 free distilled water from a wash bottle between determinations; do not bump glass electrodes on bottom or side of container because they are fragile, record pH in notebook to nearest 0.01 pH unit

Sodium Chloride, Sodium Acetate, Sodium Sulfate, Sodium Bisulfate, Sodium Carbonate, Ammonium Chloride, and Ammonium Acetate

Mix it all together and neutralize with 1 m HCL or 1 M NaOH and flush salt down sink with water

Acetic Acid, Ammonia, Hydrochloric Acidl do not leave electrodes immersed in ammonia; only leave electrodes in solution long enough to determine pH, raise and rinse and store them in 7 pH buffer pr dotslled water

The basic solutions chemically attack the glass of the electrode.