Acids and Bases

Vocabulary

amphiprotic

able to act as both a proton donor and a proton acceptor

analyte

solution being analyzed (titrated) to determine its concentration

Brønsted-Lowry acid

compound that can donate a proton to another compound in solution

Brønsted-Lowry base

compound that can accept a proton from another compound in solution

buret

type of graduated tube with a stopcock at the end that allows fine control of the release of the titrant

conjugate acid

molecule or ion formed when a Brønsted-Lowry base has accepted a proton

conjugate base

molecule or ion remaining after a Brønsted-Lowry acid donates its proton to another molecule or ion

equivalence point

pH at which all of the acid or base molecules in an acidic or basic solution have been neutralized

gravimetric analysis

analysis using the mass of a precipitate formed by a reaction to determine the starting concentration

indicator

chemical that undergoes a color change near or at the equivalence point in a titration

ionization constant

ratio of concentration of products to reactants at equilibrium. It can be used to calculate the strength of an acid or a base

Le Chatelier's principle

principle that states that a change in the temperature, pressure, or concentration of a component will cause the equilibrium condition of a chemical system to change in a way that reduces the change

neutral

having equal concentrations of H+ and OH ions in a solution

pH

measure of the concentration of H+ (or H3O+) ions in solution; pH=log[H3O+]\rm{pH}=-\log\left[{\rm{H_3O^+}}\right]

pOH

measure of the concentration of OH ions in solution; pOH=log[OH]\rm{pOH}=-\log\left[{\rm{OH^-}}\right]

strong acid or base

acid or base that completely dissociates and has a pH close to one end of the spectrum. Strong acids have a large Ka, and strong bases have a large Kb.

titrant

solution of known concentration that is used to neutralize a solution of unknown concentration (the analyte) in order to determine its concentration

titration

quantitative method that relies on measuring the volume of a solution of a known concentration necessary to neutralize a given volume of acid or base

weak acid or base

acid or base in which only a fraction of the molecules dissociates, resulting in a low concentration of H+ or OH ions and a pH closer to the middle of the range