Chapter 17

Buffer

Buffer

Solution that has a base and an acid existing at the same time

buffers can only be made with

a weak acid

a buffer resists

changes in ph when limited amounts of acid or base are added to it

henderson hasselbach equation is used

only to calculate ph in buffers

henderson hasselbach equation

pH = pka + log (A)/(HA)

strong acid strong base ph end point

14

weak acid strong base ph end point

ph >7

weak base strong acid ph

ph < 7

ksp

equilibrium constant for the solubility of a slightly soluble salt

molar solubility

moles per liter of the salt dissolved in water

ion product

the product of ion concentrations in asolution, each concentration raised to a power equal to the number of ions in the formula of the ionic compound

Qc < ksp

no precipitate forms, unsaturated solution

Qc > ksp

precipitate will occur, saturated solution

Qc = Ksp

saturated solution, no precipitate formed

salts are more soluble

at a low ph

solubility is affected by

the ph of the solution

complex ion

formed from a metal ion with lewis bases attached to it by coordinate covalent bonds

complex

compound containing complex ions

ligand

lewis base that bonds to a metal ion to form complex ions

formation constant (Kf)

equilibrium constant for the formation of a complex ion

dissociation constant (kd)

1/kF