Chapter 16 - Buffers

Question 1

A buffer contains a (weak/strong) acid/base and its conjugate base/acid

Answer 1

weak

Question 2

The base/acid ratio should be between …

Answer 2

0.10-10

Question 3

adding base to a solution would (increase/decrease) the pH

Answer 3

increase

Question 4

adding acid to a solution would (increase/decrease) the pH

Answer 4

decrease

Question 5

a buffer is most effective when concentrations of acid and base are (equal/different)

Answer 5

equal

Question 6

a buffer is most effective when concentrations of acid and conjugate base are (low/high)

Answer 6

high

Question 7

the effective range for a buffering system is ____ pH unit on either side of pKa

Answer 7

one

Question 8

the amount of acid or base that you can add to a buffer without causing a large change in pH

Answer 8

buffer capacity

Question 9

buffer capacity increases with (increasing/decreasing) absolute concentrations of the buffer components

Answer 9

increasing

Question 10

overall buffer capacity (increases/decreases) as the relative concentrations of the buffer components become more similar to each other

Answer 10

increases

Question 11

molar solubility

Answer 11

solubility in units of moles per liter

Question 12

the solubility of an ionic compound is (higher/lower) in a solution containing a common ion than in pure water

Answer 12

lower

Question 13

the solubility of an ionic compound with a strongly basic or weakly basic anion (increases/decreases) with increasing acidity (decreasing pH)

Answer 13

increases

Question 14

the solution is unsaturated and more of the solid ionic compound can dissolve in the solution

Answer 14

Q

Question 15

the solution is saturated. the solution is holding the equilibrium amount of the dissolved ions and additional solid does not dissolve in the solution

Answer 15

Q = Ksp

Question 16

the solution is super saturated. under most circumstances, the excess solid precipitates out of a super saturated solution

Answer 16

Q > Ksp

Question 17

the equilibrium constant associated with the reaction for the formation of a complex ion

Answer 17

formation constant (Kf)

Question 18

the solubility of an ionic compound containing a metal cation that forms complex ions (increases/decreases) in the presence of Lewis bases that complex with the cation

Answer 18

increases

Question 19

Stuff to know:

Answer 19

• we can determine the pH of a buffer solution by solving an equilibrium problem, focusing on the common ion effect, or by using the Henderson-Hasselbalch equation

Question 20

what is Ksp?

Answer 20

the solubility product constant - an equilibrium constant for the dissolution of an ionic compound in water