Chapter 13 + 16 - Equilibrium + Ksp

Question 1

What does it mean when K > 1, K < 1, and when K = 1? (ratios) What does this mean?

Answer 1

K>1 means that there will be many more products than reactants at equilibrium; reaction essentially goes to completion
K<1 means that there are more reactants than products at equilibrium; reaction does not occur significantly
K=1 means that the ratio of reactants to products is equal at equilibrium

Question 2

Define Q

Answer 2

Q= the reaction quotient/”k” at a SPECIFIC TIME (best defined as reaction progress)

Question 3

What does it mean when Q >k, <k, or = k?

Answer 3

> k system shifts left
< k system shifts right
= k system does not shift, is at equilibrium

Question 4

What happens when the concentration/pressure of one or more of the products/reactants is zero?

Answer 4

Reaction shift towards the missing component

Question 5

Homogenous vs. heterogenous equilibria

Answer 5

Homogenous: Same phase (ex. HCN(aq) <–> H+(aq) + CN-(aq)
Heterogeneous: Involves more than one phase

Question 6

What kind of substances have no impact on the position of heterogeneous equilibrium? Why?

Answer 6

Pure solids and liquids due to having a constant concentration

Question 7

Kc vs. Kp (not the equation)

Answer 7

Kc - Constant of concentrations of substances
Kp - Constant of partial pressures of concentrations

Question 8

Equation relating Kc and Kp:

Answer 8

Kp = Kc (RT)^change in n

Question 9

Reactant-favored vs. product favored (which is right, which is left?

Answer 9

Reactant - position lies to the left
Product - Position lies to the right

Question 10

When asked for equilibrium concentration/pressure in relation to initial use a…

Answer 10

ICE box

Question 11

When one or more concentrations/pressures are mentioned but others are not in q question, the values of the unmentioned substances are:

Answer 11

0

Question 12

Anything divided by 0 is…

Answer 12

infinitely large (undefined)

Question 13

In the ICE box method _______ (always/never) use coefficients to determine the concentration x values coefficients.

Answer 13

always

Question 14

What is Ksp? How does it compare to solubility?

Answer 14

Ksp = solubility product

Ksp is the ratio of products:reactants at equilibrium

Question 15

What is a conjugate?

Answer 15

Anion

Question 16

Do strong acids form in solution? WHy or why not?

Answer 16

No, because they 100% dissociate they will never associate while in sol’n

Question 17

What happens when Q>Ksp? When Q<Ksp and Q=Ksp?

Answer 17

Q>Ksp - Precipitation forms
Q<Ksp - No precipitation
Q=Lsp - No precipitate but maximum saturation of ions in sol’n

Question 18

Pure solids/liquids _____ (do/do not appear) in the equilibrium expression

Answer 18

do not appear

Question 19

k vs. K (AUTHORS NOTE EDIT)

Answer 19

k = rate constant
K = equilibrium constant, =

Question 20

K or the equilibrium constant is _____-dependent. Why?

Answer 20

temperature, changing it will give the products and reactants new rates, and thus new concentrations at equilibrium.

Question 21

What is the effect of catalysts/increasing surface area on equilibrium position?

Answer 21

None, they speed up rate of rxn in BOTH sides, maintaining K

Question 22

Why do salts like AgCl have the same solubility in acid as they do in water?

Answer 22

Cl- is the conjugate of strong acid, strong acid will not form in water and instant 100% dissociate even if it did

Question 23

What happens when Q (ion product) is >, <, and = Ksp? Also, what makes Q special?

Answer 23

Q is Ksp but w/initial concentrations
Q> Ksp = precipitation, too many reactants to dissolve
Q< Ksp = no precipitation
Q = Ksp = at equilibrium, MAXIMUM saturation b4 precipitation

Question 24

Define le chatelier’s principle

Answer 24

a rxn at equilibrium will respond to eligible changes by increasing product or reactant reaction rates

Question 25

When adding two equations the K is…

Answer 25

multiplied

Question 26

How does changing the coefficient across a reaction change the K?

Answer 26

K is raised to the power of the multiplier of the equation

Question 27

Common ion effect

Answer 27

Same ions on one side, rxn shifts away from that one side

Question 28

relationship between Kc and Kp

Answer 28

Kp = Kc(RT)^delta n

Question 29

Units for K and Q

Answer 29

nothing