Rice Rice Baby
2A(g) + B(g) ⇌ 2C(g)
The initial concentrations of A and B are 0.042M. What is the equilibrium constant if the concentration of A at EQ is 0.0124?
R 2A(g) + B(g) ⇌ 2C(g)
I 0.0420 0.0420 0
C -2x -x 2x
E 0.0420 - 2x 0.0420 - x 2x
0.042 - x = 0.0124
x = 0.0148
EQ Concetrations:
A = 0.0124, B = 0.0272, C = 0.0296
0.02962/(0.01242)(0.0272) = 209
Give a real good definition of Le Chatelier's principle
Le Chatelier’s principle describes the process by which an equilibrium exposed to a stress will shift so as to relieve that stress and regain equilibrium.
2A + 3B ⇌ 3C
At EQ, the concentrations of A, B, and C are 0.0032M, 0.0086M, and 0.0101 M respectively. Calculate the EQ constant
Kc = (0.0101)3/(0.0032)2(0.0086)3
Kc = 1.582 x 105
I2 (aq) + I- (aq) ⇌ I3- (aq)
If a solution with the concentrations of I2 and I- both equal 1.00 x 10^-3 before the reaction gives an equilibrium concentration of I2 of 6.61 x 10^-4 M, what is the equilibrium constant for the reaction? (There is not initial I2)
R I2 (aq) + I- (aq) ⇌ I3- (aq)
I 1.00 x 10^-3 1.00 x 10^-3 0
C -x -x +x
E 1.00 x 10^-3-x 1.00 x 10^-3-x x
1.00 x 10^-3 - x = 6.61 x 10^-4
x = 3.39 x 10^-4 M
Kc = [I3-] / [I2][I-] = 3.39 x 10^-4 / (6.61 x 10^-4)(6.61 x 10^-4)
Kc = 776
CO2(g)+H2(g)⇌CO(g)+H2O(g)
What will happen if the volume suddenly decreased?
Nuthin
3A + B ⇌ 2C
If EQ concentrations are [A] = 0.66M, [C] = 2.9M and Kc = 24.6, calculate EQ concentration of B
Kc = [C]2/[A]3[B]
24.6 = (2.92)/(0.663)[B]
[B] = 1.2 M
CH3CO2H + C2H5OH ⇌ CH3CO2C2H5 + H2O
The equilibrium constant for this reaction is 4.0
What are the equilibrium concentrations when a mixture that is 0.15 M CH3CO2H, 0.15 M C2H5OH, 0.40 M CH3CO2C2H5, and 0.40 M H2O are mixed in enough dioxane to make 1.0L of solution?
R CH3CO2H + C2H5OH ⇌ CH3CO2C2H5 + H2O
I 0.15 0.15 0.40 0.40
C +x +x -x -x
E 0.15+x 0.15+x 0.40-x 0.40-x
Kc = [CH3CO2C2H5][H2O]/[C2H5OH][CH3CO2H]
4.0 = (0.40-x)(0.40-x)/(0.15+x)(0.15+x)
Take the square root of the whole problem
2.0 = 0.40 - x / 0.15 +x
x = 0.033
Use X to calculate EQ concentrations
What does it mean if a reaction is exothermic?
(Is ∆H + or -, is heat a product or reactant, ect...)
∆H is negative, heat is a product
2A+B → C+2D
If the change in concentration for C is 0.36M, what will be the change in concentration for A?
HINT: Look at the stoichiometry :)
-0.72M
H2 (g) + I2 (g) ⇌ 2HI(g)
The equilibrium constant for the reaction is 50.5 under uhhh some conditions
What are the EQ concentrations if the initial concentration is 1.00 M H2 and 2.00M I2?
R H2 (g) + I2 (g) ⇌ 2HI(g)
I 1.00M 2.00M 0
C -x -x +x
E 1.00-x 2.00-x +2x
Kc = 2x2 /(1.00-x)(2.00-x) = 50.5
2x2 = 50.5(1.00-x)(2.00-x)
WOLFRAM ALHPA WOO!
x = 0.964
Use X to calculate EQ concentrations
What happens when more reactant is added to a chemical system at equilibrium? (What is the magnitude of Q as compared to K? How is EQ restored? What happens to the concentrations of the other reactants?)
When more of a reactant is added to a chemical system at equilibrium, it causes the value of Q to be lesser than the value of K. The forward reaction proceeds faster than the reverse reaction until equilibrium is attained.
PCl5 (g) ⇌ PCl3 (g) + Cl2 (g)
Determine the EQ concentrations of the reactants if Kc = 0.0211 and the initial concentration of PCl5 (g) = 1.00M
R PCl5 (g) ⇌ PCl3 (g) + Cl2(g)
I 1.00 0 0
C -x x x
E 1.00-x +x +x
Kc = [PCl3][Cl2]/[ PCl5]
0.0211 = (x)(x)/(1.00-x)
0.0211(1.00-x) = x2
x2 + 0.0211x-0.0211 = 0
(Plug that into the quadratic formula)
x = 0.135 and -0.156
The answer cannot be -0.156, so the reactant concentrations are
0.135 M