Equilibrium

Question 1

what happens if you add a reactant:

Answer 1

shifts RIGHT & Q<K

Question 2

what happens if you remove reactant:

Answer 2

shifts left & Q>K

Question 3

what happens if you add product:

Answer 3

shifts left & Q>K

Question 4

what happens if you remove product:

Answer 4

shifts right & Q<K

Question 5

what happens if you decrease the volume?

Answer 5

increase pressure, so it shifts to side with fewer gas molecules

Question 6

what happens if you increase volume?

Answer 6

decrease pressure, so it shifts to side with more gas molecules

Question 7

what happens if you add heat during endothermic reaction?

Answer 7

heat is reactant- shifts right

Question 8

what happens if you add heat during exothermic reaction?

Answer 8

heat is product- shifts left

Question 9

what happens if Q is greater or less than K?

Answer 9

Q>K: shift left
Q<K: shift right

Question 10

what does a positive or negative Kc indicate?

Answer 10

positive: favor product
negative: favor reactant

Question 11

what happens when delta H is negative and delta S is positive?

Answer 11

at any temperature is spontaneous

Question 12

what happens when delta H is positive and delta S is negative?

Answer 12

nonspontaneous at any temperature

Question 13

what happens when delta H is negative and delta S is negative?

Answer 13

spontaneous at low temperatures and non spontaneous at high temperatures

Question 14

what happens when delta H is positive and delta S is positive?

Answer 14

nonspontaneous at low temperatures and spontaneous at high temperatures

Question 15

what happens to a buffer of HX/X- when a strong acid is added:

Answer 15

X- + H+ -> HX (weak acid) so [X-] decrease and [HX] increase

Question 16

what happens to a buffer of HX/X- when strong base is added:

Answer 16

OH- + HX -> X- + H2O so [X-] increase and [HX] decrease

Question 17

what will a CB of a strong acid and CA of weak base do?

Answer 17

ph <7

Question 18

what will a CB of a weak acid and CA of weak base do?

Answer 18

pH increase or decrease depending on which stronger

Question 19

what will a CB of a strong acid and CA of strong base do?

Answer 19

pH=7

Question 20

what will a CB of weak acid and CA of strong base?

Answer 20

pH >7

Question 21

what happens to delta G when Q changes in the Nernst Equation?

Answer 21

Q large -> delta G more positive so less spontaneous in forward
Q small -> delta G more negative so more spontaneous in forward

Question 22

what happens if delta G knot is negative?

Answer 22

Keq= big so product favored

Question 23

what happens if delta G knot is positive?

Answer 23

Keq= small so reactant favored