Buffers Ch 17

Question 1

important buffer in blood

Answer 1

mixture of carbonic acid (H2CO3) and the bicarbonate ion (HCO3^-), one neutralizes added base and the other neutralizes added acid

Question 2

low blood pH

Answer 2

acidosis, where acid affects equilibrium between hemoglobin and oxygen, which can kill, but can save by adding ethyl alcohol to the dangerous ethylene glycol

Question 3

buffer definition

Answer 3

resists pH change by neutralizing acid or base, has significant amounts of both weak acid and its conj. base or significant amounts of weak base and its conj. acid - weak acid neutralizes added base and weak base neutralizes added acid

Question 4

buffer ex

Answer 4

HC2H3O2 and NaC2H3O2, acetic acid and sodium acetate

Question 5

common ion effect

Answer 5

tendency for a common ion to decrease solubility of ionic compound or decrease ionization of weak acid or base, following Le Chat.

Question 6

calculating pH change in buffer solition

Answer 6

do stoic calculation - where find how addition changes amounts of acid and conj. base, and then do equil. calculation - find pH based on new amounts of acid and conj. base

Question 7

in buffer solutions amount of H+

Answer 7

not exactly 0 but is close enough to approximate as 0

Question 8

substitution in buffer solution, ratio

Answer 8

can substitute amounts of acid and base in moles in place of concentration because volume is same for acid and base in the buffer solution

Question 9

when calculating pH of buffer after adding small amounts of acid or base, note

Answer 9

adding small amounts of strong acid to buffer convers stoic. amount of base to conj. acid and decreases pH of buffer
adding small amounts of strong base to buffer converts stoic amount of acid to conj. base and increases pH of buffer