Chapter 7

Question 1

dynamic equilibrium

Answer 1

Closed system
- energy may be transferred but cannot leave/enter the system

Question 2

types of equillibrium

Answer 2

1. solubility
2. phase
   chemical reaction

Question 3

solubility equilibrium

Answer 3

• conc. of dissolved solute is constant, the rate of dissolution and crystallization are equal

Question 4

phase equillibrium

Answer 4

• two or more states of a pure substance in fymanic equilibrium (can only occur at melting/freezing point)

Question 5

chemical equation equilibrium

Answer 5

• reactants and products are produced at the same rate, limits amount of products

Question 6

when do you know you are at equilibrium

Answer 6

1. system is closed
2. all species are present
3. the reaction is reversible
4. no visible changes
5. both forward and reverse reactions are occurring at microscopic level
6. forward and reverse reaction rates are equal (rate f= rate r)

Question 7

what is the equillibirum constant

Answer 7

-K
- dependent on temp
not dependant on conc.

Question 8

what is the equilibrium law statement

Answer 8

Keq= (C)^c(D)^d/ (A)^a(B)^b

Question 9

homogenous equillibria

Answer 9

all reactants and products are of the same matter

Question 10

heterogeneous eqillibria

Answer 10

• present in at least two different states of matter
• if pure soilds or liquids are involved their conc. is not included in the law equation because their conc.s can not change in a sealed reaction vessel

Question 11

the magnitude of equillibrium constant

Answer 11

-very large value indicates position towards the right
- at equilibrium the products will outweigh he reactants

k> 1- favours products
k=1- similar
k<1- favaours reactants

Question 12

lechantleirs principle

Answer 12

when you apply stress the system will try to oppose it and relieve the stress

(ex if you add products it will produce more reacntants)

Question 13

reaction quotient (Q)

Answer 13

value obtained by subsitutiong inital conc. into equilibrium expression

Question 14

determining direction of reaction

Answer 14

Q>K: shift left beacuse too much products
Q=K: at equilibrium
Q<K: shift right because too much reactanrs

Question 15

the 100 rule

Answer 15

(inital conc of reactants/k)>100

you can safely assume that the value of x is so small that it is negligible and wont make a different, drop the x in denominator

Question 16

common ion effect

Answer 16

decrease in solubility which occurs when an ionic compound is dissolved in a solution that contains an ion in common with the solid
(consistent principle of le chatelier)

Question 17

ice tables

Answer 17

• cells are filled with concentrations

Question 18

trial product Q

Answer 18

if Q is greater than the soloubility product constant Ksp, a substance will precipitate