To aubrey, jona, bahemm, CHE 121 Chap 6 Reviewers

Question 1

State in which there are no observable changes
with time

Answer 1

Equilibrium

Question 2

Chemical Equilibrium is achieved when:

Answer 2

• Rates of the forward and reverse reactions are equal and
• Concentrations of the reactants and products remain
  constant
• Dynamic equilibrium

Question 3

Gibbs energy tends to minimum at?

Answer 3

ΔT = 0, ΔP =0

Question 4

At constant temperature and pressure:

Answer 4

• ΔGrxn < 0 ; forward rxn spontaneous (Exergonic)
• ΔGrxn > 0 ; reverse rxn spontaneous (Endergonic)
• ΔGrxn = 0 ; rxn at equilibrium (Neither)

Question 5

A strongly exergonic process can drive a _____ endergonic process

Answer 5

weaker

Question 6

Based on Law of Mass Action, Equilibrium will

Answer 6

Lie to the right & Favor products if K > 1

Lie to the left & Favor reactants if K < 1

Question 7

Ways of Expressing Equilibrium Constants

Answer 7

• Heterogeneous equilibria
• Homogeneous equilibria

Question 8

Applies to reactions in which
reactants and products are in different phases

Answer 8

Heterogenous equilibrium

Question 9

In heterogeneous equilibrium, the concentration of solids and pure liquids_____in the expression for the equilibrium constant

Answer 9

are not included

Question 10

Applies to reactions in which all
reacting species are in the same phase

Answer 10

Homogenous equilibrium

Question 11

How does equilibria respond to pressure?

Answer 11

ΔG = -RT ln K

Defined at a single standard pressure, 1 bar. Therefore, K is independent of pressure. However, equilibrium composition is NOT necessarily pressure-independent.

Question 12

Two ways to pressurize a gas:

Answer 12

• Vapour plus inert pressurizing gas
  -Piston permeable to vapour but not to liquid

Question 13

Le Chatelier’s principle:

Answer 13

If an external stress is applied to
a system at equilibrium, the
system will adjust itself in order
to minimize the stress

Question 14

How does equilibria respond to temperature

Answer 14

From Le Chatelier’s principle for a system at equilibrium:
* System will shift in endothermic direction as T increases
* System will shift in exothermic direction as T decreases

Question 15

Type of reaction in which an increased T favors reactants

Answer 15

Exothermic reactions

Question 16

Type of reaction in which an increased T favors products

Answer 16

Endothermic reactions

Question 17

It has the dimensions of amount of substance and is reported in moles, ξ (xi)

Answer 17

Extent of reaction;

Question 18

Is defined as the slope of the
graph of the Gibbs energy plotted against the extent of reaction:

Answer 18

Reaction Gibbs energy, ΔrG

Note: Delta sign means derivative (Not difference in values)

Question 19

Condition of Equilibrium

Answer 19

∆rG = 0

The spontaneous direction of reaction lies in the direction of decreasing G. The slope is zero, and the reaction is at equilibrium and spontaneous in neither direction,

Question 20

Ratio of activities of products and activities of reactants. It is also a combination of activities used
to express the current value of the reaction Gibbs energy.

Answer 20

Reaction Quotient, Q

Question 21

An equilibrium constant K expressed in terms of activities is called a

Answer 21

Thermodynamic equilibrium constant

Note: Because activities are dimensionless, the thermody-
namic equilibrium constant is also dimensionless.

Question 22

The degree of dissociation (or extent of dissociation, α) is defined as

Answer 22

The fraction of reactant that has decomposed;

Question 23

Is the value of the reaction
quotient at equilibrium.

Answer 23

Equilibrium constant

Question 24

Lastly, complete the statement. Shikata….

Answer 24

ga nai

Believe you can and you’re halfway there - Roosevelt

“When things go wrong, as they sometimes will, When the road you’re trudging seems all uphill, When the funds are low and the debts are high, And you want to smile, but you have to sigh, When care is pressing you down a bit,
Rest, if you must, but don’t you quit. - John Greenleaf Whittier

To Aubrey, Bahem, Jona,

Hinaut naa pa mo ani na cards para mabasahan pa ni. Okay lang pud kung dili na hehe. Hapit na gyud ta sa finish line. Hangak na kaayo pero kung atu lantawun, layo na gyud tag nalakwan sa life. 3rd yearr na tayoo. Wala gyud kuy control sa atu situation runn. If ever naa lang kuy magic, ipapasar nako kita tanann. You are always included sa ako prayers, na makapasar unta tayo no matter unsa ka lisud ang umaabot na problems. Wala ko dira sa inyu physically pero I know makaya na ninyu kay naa kayo tulo kumpleto dira. God bless sa inyuuu tulo. Mas giant pa mo compared sa themo. God bless guys, uncertain kay atu future, but but one thing is for sure, naa ra mi dari para ninyu. You are not alone in this fight. Unsure pa sad kung nakapasar ko, but wala na sad ko mabuhat pero sige lang, come what may. All of the besttt sa inyuu, aubreyyy, jonaaa, bahemmm. Buhaton nako tanan ug ihatag nako ako mahelpp para maka graduate tayo on timee gyudd hantud sa ako makaya, labyuuu

-Abdul :))