Solubility
What is the solubility constant for the following equation?
Fe(OH)3(s) → ← Fe3+(aq) + 3 OH–(aq)
Ksp = [Fe3+]e[OH–]e3
Given the equilibrium equation below:
A2(g)+ B2(g)⇋2AB(g) If, at equilibrium, the concentrations are as follows:
[A2]=3.45M, [B2]=5.67M and [AB]=0.67M
a) Write the expression for the equilibrium constant, Keq
b) Find the value of the equilibrium constant, Keq at the temperature that the experiment was done.
0.023
a) HNO3+H2O⟶H3O++NO3−
identify the conjugate acid and conjugate base
CB: NO3-
CA: H30+
What is a strong acid? Give an example
An acid that completely dissociates in solution
HCl
What is the molarity of a solution that was prepared by dissolving 14.2 g of NaNO3
(molar mass = 85.0 g/mol) in enough water to make 350 mL of solution?
0.477
Consider the equilibrium: 2SO(g) +02(g) →2SO,(g) K. =4.36 M
Calculate the value of "Q" for a situation in which the concentrations are [SO,] = 2.00 M, [O,] = 1.50 M, and [SO,] = 1.25 M.
0.260
c) HS−+H2O⟶H2S+OH−
Identify the conjugate acid and conjugate base
CA: H2S
CB: OH-
What is a strong base?
A base that completely dissociates in solution
NaOH
How many grams of NaBr (molar mass = 102.9 g/mol) would be needed to prepare 700
ml of 0.230 M NaBr solution?
16.6 g NaBr
2NO(g)+O2 (g)⇌2NO2 (g)
M
[NO]=0.5M
[O2]=0.2M
[NO2]=0.8
12.8
The ionization constant for water (Kw) is 9.311 × 10−14 at 60 °C. Calculate [H3O+], [OH−], pH, and pOH for pure water at 60 °C.
x = 3.051 × 10−7 M = [H3O+] = [OH−]; pH = −log3.051 × 10−7 = −(−6.5156) = 6.5156; pOH = pH = 6.5156
A ph of 7.1 is acidic, neutral or basic?
Basic
If you dilute 175 mL of a 1.6 M solution of LiCl to 1.0 L, determine the new concentration of the solution.
M1V1 = M2V2
(1.6 mol/L) (175 mL) = (x) (1000 mL)
x = 0.28 M
What is the value of the equilibrium constant at 500 °C for the formation of NH3 according to the following equation?
N2(g)+3H2(g)⇌2NH3(g)
An equilibrium mixture of NH3(g), H2(g), and N2(g) at 500 °C was found to contain 1.35 M H2, 1.15 M N2, and 4.12 × 10−1 M NH3.
6x10-2
What are the hydronium and hydroxide ion concentrations in a solution whose pH is 6.52
3.019 x 10-7
3.31x10-8
How does temperature affect pH?
Makes it more acidic
To what volume should you dilute 133 mL of an 7.90 M CuCl2 solution so that 51.5 mL of the diluted solution contains 4.49 g CuCl2?
1) Find moles:
(4.49g CuCl2) (1 mole CuCl2 / 134.45 grams) = 0.033395 moles CuCl2
2) Find the molarity of the 51.5 mL of the diluted solution that contains 4.49g CuCl2:
(0.033395 moles CuCl2) / (0.0515 liters) = 0.648 M
3) Use the dilution formula:
M1V1 = M2V2
(7.90 M) (133 mL) = (0.648 M) (V2)
V2 = 1620 mL
You should dilute the 133 mL of an 7.90 M CuCl2 solution to 1620 mL.
Hydrogen is prepared commercially by the reaction of methane and water vapor at elevated temperatures.
CH4(g)+H2O(g)⇌3H2(g)+CO(g)
What is the equilibrium constant for the reaction if a mixture at equilibrium contains gases with the following concentrations: CH4, 0.126 M; H2O, 0.242 M; CO, 0.126 M; H2 1.15 M, at a temperature of 760 °C?
6.4
What is a buffer?
Calculate the pH of a buffer solution containing 0.1 M acetic acid (CH3COOH) and 0.2 M sodium acetate (CH3COONa). The pKa of acetic acid is 4.76
A solution made up of a weak acid and its conjugate base OR a weak base and its conjugate acid
Identify the components: [A-] is the acetate ion (CH3COO-) from sodium acetate, and [HA] is the acetic acid (CH3COOH).
Plug into the equation: pH = 4.76 + log(0.2 M / 0.1 M)
Calculate: pH = 4.76 + log(2) = 5.06
Who is the best SI leader in the entire world? Not a trick question
Me, duh!