Equillibrium

Question 1

(The Equilibrium Constant) Formula for Kc

[Note: aA + bB ⇌ dD + eE]

Answer 1

Kc = [D]ᵈ[E]ᵉ/[A]ᵃ[B]ᵇ

Question 2

(The Equilibrium Constant) Formula for Kp [Note: P is partial pressure]

Answer 2

Kp = (PD)ᵈ(PE)ᵉ/(PA)ᵃ(PB)ᵇ

Question 3

(The Equilibrium Constant) Conversion between Kp and Kc

Answer 3

Kp=Kc(RT)^ⁿ

R = Ideal Gas Constant = 0.0821
T = Temperature in Kelvin
^ⁿ = Change in n = (moles of gaseous products)-(moles of gaseous reactants)

Question 4

(Qualities of Keq) Keq > 1

Answer 4

Mostly products; equilibrium lies far to the right.

Question 5

(Qualities of Keq) Keq < 1

Answer 5

Mostly reactants; equilibrium lies far to the left.

Question 6

(Qualities of Keq) Keq = 1

Answer 6

Roughly equal amounts of reactant and product; equilibrium lies in the middle.

Question 7

(Qualities of The Reaction Quotient) Q > Keq

Answer 7

The reaction is not in equilibrium and will proceed to the left (increase concentration of reactants).

Question 8

(Qualities of The Reaction Quotient) Q < Keq

Answer 8

The reaction is not in equilibrium and will proceed to the right (increase concentration of products).

Question 9

(Qualities of The Reaction Quotient) Q = Keq

Answer 9

The system is at equilibrium.

Question 10

(Le Chatelier’s Principle) Stress from Increasing Pressure

Answer 10

If the PRESSURE in a system at equilibrium INCREASES, Q changes and the equilibrium will SHIFT TOWARD the side with FEWER MOLES OF GAS.

Question 11

(Le Chatelier’s Principle) Stress from Decreasing Pressure

Answer 11

If the PRESSURE in a system at equilibrium DECREASES, Q changes and the equilibrium will SHIFT TOWARD the side with MORE MOLES OF GAS.

Question 12

(Le Chatelier’s Principle) Stress from Increasing Concentration

Answer 12

If the CONCENTRATION in a system at equilibrium INCREASES, Q changes and the equilibrium will SHIFT TOWARD the side that will REDUCE THE CONCENTRATION.

Question 13

(Le Chatelier’s Principle) Stress from Decreasing Concentration

Answer 13

If the CONCENTRATION in a system at equilibrium DECREASES, Q changes and the equilibrium will SHIFT TOWARD the side that will INCREASE THE CONCENTRATION.

Question 14

(Le Chatelier’s Principle) Stress from Dilution

Answer 14

If SOLVENT IS ADDED to a system at equilibrium, Q changes and the equilibrium will SHIFT TOWARD the side with MORE PARTICLES to reduce that stress.

Question 15

(Le Chatelier’s Principle) Quirk of Stress from Change in Temperature

Answer 15

Changes in temperature change the equilibrium constant (Keq).

Question 16

(Le Chatelier’s Principle) Stress from Decreasing Temperature

Answer 16

Cooling (taking heat away) shifts the equilibrium in the direction that produces heat; Keq increases.

Question 17

(Le Chatelier’s Principle) Stress from Increasing Temperature

Answer 17

Adding heat (increasing the temperature) shifts the equilibrium in the direction that absorbs heat; Keq decreases.