CH 14 (Chemical Equilibrium)
Write the equilibrium expression for Kc for the following reaction:
N2(g) + 3 H2 (g) ⇌ 2 NH3 (g)
Kc = [NH3]^2 / [N2] [H2]^3
Each of the following pairs contains one strong acid and one weak acid EXCEPT:
A) H2SO4 and H2CO3
B) HNO3 and HNO2
C) HBr and H3PO2
D) HSO4^- and HCN
D) HCl and H2S
D) HSO4^- and HCN
Calculate the molar solubility of AgCl (Ksp = 1.8 x 10^-10) at 25 degrees in pure water
s = 1.3 x 10^-5
For the equilibrium 2 SO3(g) ⇌ 2 SO2(g) + O2(g), Kc is 4.08 x 10^-3 at 1000 K. Calculate the value for Kp.
R = 0.08206 L*atm/mol*K
Which one of the following salts forms aqueous solutions with pH = 7?
A) Na2S
B) NaBr
C) NaClO2
D) NaNO2
E) Na2CO3
B) NaBr
Calculate the pH of the solution formed when 45.0 mL of 0.100 M NaOH is added to 50.0 mL of 0.100 M CH3COOH (Ka = 1.8 x 10^-5).
pH = 5.70
The equilibrium constant for the formation of hydrogen iodide from hydrogen and iodine is 45 at a certain temperature. H2(g) + I2(s) ⇌ 2 HI(g). Kc = 45
Which of the following is true regarding this equilibrium?
I. The reaction is product favored.
II. The reaction is reactant favored.
III. Equilibrium lies to the right
IV. Equilibrium lies to the left
A) I and III
B) I and IV
C) II and III
D) II and IV
E) None are true, as the concentrations of reactants and products are the same
A) I and III
What is the concentration of [OH-] in a 0.20 M solution of ammonia? The Kb value for ammonia is 1.8 x 10^-5
1.9 x 10^-3 M
A buffer solution is prepared by mixing 0.250 moles of acetic acid (HC2H3O2) and 0.250 moles of sodium acetate (NaC2H3O2) in enough water to make 1.50 L of the buffer. The initial pH of the buffer is 5.00. Calculate the pH of the buffer solution after 0.015 moles NaOH are added.
pH = 5.08
A 1.000-L flask is filled with 1.000 mol of H2 and 2.000 mol of I2 at 448 °C. The value of the equilibrium constant Kc for the reaction H2(g) + I2(g) ⇌ 2HI(g) at 448 °C is 50.5. What are the equilibrium concentrations of H2, I2 and HI in moles per liter?
[H2] = 0.065 M
[I2] = 1.065 M
[HI] = 1.87 M
What is the pH of a 0.20 M solution of sodium acetate? The Ka for acetic acid is 1.8 x 10^-5?
Kw = 1.0 x 10^-14
pH = 9.04
FInd the pH at each of the following points in the titration of 25 mL of 0.3 M HF with 0.3 NaOH. The Ka value is 6.6 x 10^-4.
A) The initial pH
B) After adding 10 mL of 0.3 NaOH
C) After adding 12.50 mL of 0.3 NaOH
D) After adding 25 mL of 0.3 NaOH
E) After adding 25 mL of 0.3 NaOH
A) 1.68
B) 3.00
C) 3.18
D) 8.18
E) 11.77