Unit 1
If 0.42 g of NaNO3 is dissolved to make 50.0 mL of solution, calculate the solution's concentration in Molarity (M).
0.0988 M
Solve for the hydronium ion concentration, the hydroxide ion concentration, and the pH of a 0.10 M HBr aqueous solution
[H3O+] = 0.10 M; pH = 1.00
[OH-] = 1.0 x 10-13 M
After mixing an excess PbBr2 with a fixed amount of water, it is found that the equilibrium
concentration of Pb2+ is 1.6 × 10 –2 M. What is Ksp for PbBr 2
1.64 x 10-5
What is the equation for rate law?
Rate = k[A]m[B]n
Thursday
What is the boiling point elevation of a solution containing 2 moles of solute in 1000g of water? (Kb for water = 0.512 °C/m)
1.024 °C
Calculate the change in internal energy (ΔU) for a system that absorbs 250 J of heat and performs 100 J of work on the surroundings.
150 J
Silver chromate (Ag₂CrO₄) has a Ksp of 1.1 × 10⁻¹².
Calculate the molar solubility of Ag₂CrO₄ in pure water.
6.50×10−5mol/L
What is the difference between an intermidiate and a catalyst?
A catalyst speeds up a reaction without being consumed, while an intermediate is formed and used up during the reaction but does not appear in the overall equation.
Write the Kp expressions for the following reaction:
N2(g)+3H2(g)⇌2NH3(g)
Kp= P2(NH3)/P3(H2)* P(N2)
Calculate the freezing point depression of a solution containing 5g of urea (CH4N2O) dissolved in 50g of water. (Kf for water = 1.86 °C/m)
3.09 °C
For the reaction N2O4(g)⇌2NO2(g), Kp = 0.14 at 25°C. If the initial pressure of N2O4 is 0.50 atm, calculate the equilibrium partial pressures of N2O4 and NO2 (Use quadratic formula to solve for X)
PN2O4 = 0.38 atm, PNO2 = 0.24 atm
A 25.0-mL sample of 1.00 M NH3 is titrated with 0.25 M HCl. What is the pH of the solution after 15.00 mL of acid has been added to the ammonia solution?
(Kb(NH3) = 1.8 x 10–5)
pH ≈ 10.01
The nuclide Nb decays by a first-order process with a rate constant of 2.96 × 10-2 h-1.
How long will it take for 86.0% of the initial amount of Nb to be consumed?
66.4 hours
Name 4 NFL teams that have the color green in their logo?
Green Bay Packers, Philadelphia Eagles, New York Jets, Seattle Seahawks,
The vapor pressure of pure water at 25°C is 23.8 torr. If 100g of sucrose (C12H22O11) is dissolved in 500g of water, what is the vapor pressure of the solution? (Molar mass of sucrose = 342.3 g/mol)
23.56 torr
What is the pH of a 0.35 M solution of methylamine (CH3NH2, Kb = 4.4 × 10–4) at 25oC?
pH = 12.09
A 100.0 mL sample of 0.10 M NH3 is titrated with 0.10 M HNO3. Determine the pH of the solution after the addition of 150.0 mL of HNO3. The Kb of NH3 is 1.8 × 10-5.
1.70
The decomposition of a compound follows first-order kinetics with a half-life of 15.0 minutes.
How much time is required for 75% of the compound to decompose?
t≈30.0minutes
A solution is made by dissolving 20.0 g of a nonvolatile solute in 100.0 g of water. The vapor pressure of pure water at 25°C is 23.8 torr. If the vapor pressure of the solution is 22.5 torr, what is the molar mass of the solute?
61.9 g/mol
An aqueous solution is 0.273 m KCl. The density of the solution is 1.011 x 10³ g/L. What is the Molar concentration of KCl? (Molar mass of KCl = 74.6 g/mol)
0.270 M
Acetic acid (CH₃COOH) is a weak acid. A 0.10 M solution is prepared. The Ka for acetic acid is 1.8 × 10⁻⁵.
Use an ICE table to calculate the [H⁺], [CH₃COO⁻], and pH at equilibrium.
2.88
Calculate the pH at the equivalence point when 50.0 mL of 0.100 M HF (Ka = 6.6 × 10⁻⁴) is titrated with 0.100 M NaOH.
pH ≈ 7.94
Which of the following changes will affect the activation energy of a reaction?
1. Increasing or decreasing the reaction temperature
2. Adding a catalyst.
3. Increasing or decreasing the reactant concentrations.
a. 1 only
b. 2 only
c. 3 only
d. 1 and 2
e. 2 and 3
B.) 2 only
Who's going to eat up the final tomorrow?
Everyone in the room!