Chem II Lab Final
Lab 6 – Kinetics
Q: How is rate expressed in terms of reactant concentration?
A: Rate = -Δ[reactant]/Δt
Q: How is rate expressed in terms of product concentration?
A: Rate = Δ[product]/Δt
Q: What is the overall reaction order?
A: The sum of all individual exponents in the rate law
Q: How can you determine individual reaction orders?
A: Use the method of initial rates and compare rate changes with concentration changes
Q: How do you write a rate law from experimental data?
A: Use rate = k[A]^m[B]^n and solve for m and n using data
Q: How does increasing concentration affect reaction rate?
A: It increases the frequency of collisions, increasing the rate
Q: How does increasing temperature affect reaction rate?
A: It increases particle energy, making collisions more effective
Q: What is the half-reaction method for balancing redox equations?
A: Split the reaction into oxidation and reduction half-reactions, balance each, and combine
Q: How is reaction rate calculated from data?
A: Rate = Δ[product]/Δt or Δ[reactant]/Δt
Q: What is the rate constant (k)?
A: A proportionality constant in the rate law dependent on temperature
Lab 7 – Coordination Complexes
Q: What is a monodentate ligand?
A: A ligand that donates one pair of electrons to the metal
Q: What is a bidentate ligand?
A: A ligand that donates two pairs of electrons to the metal
Q: How is electromagnetic radiation arranged by frequency?
A: Gamma > X-ray > UV > Visible > IR > Microwave > Radio
Q: How is electromagnetic radiation arranged by wavelength?
A: Radio > Microwave > IR > Visible > UV > X-ray > Gamma
Q: What does the color wheel help determine?
A: The complementary color of a solution based on absorbed wavelength
Q: What is the equation for energy of radiation?
A: E = hν or E = hc/λ
Q: What is the Beer-Lambert Law?
A: A = εbc
Q: What does A = εbc represent?
A: Absorbance = molar absorptivity × path length × concentration
Q: How is absorbance calculated from transmittance?
A: A = -log(T), where T = %T/100
Q: How is % transmittance calculated from absorbance?
A: %T = 10^(-A) × 100
Lab 8 – Chemical Equilibria
Q: How do you write a reaction quotient (Q)?
A: Q = [products]^coeff / [reactants]^coeff using current concentrations
Q: How do you write an equilibrium constant (Kc)?
A: Kc = [products]^coeff / [reactants]^coeff at equilibrium
Q: How do you calculate Kc from quantities?
A: Plug equilibrium concentrations into Kc expression
Q: What does Le Châtelier’s Principle state?
A: A system at equilibrium will shift to oppose a disturbance
Q: What happens to equilibrium if concentration increases?
A: The system shifts to consume the added substance
Q: Does K change with concentration?
A: No, K remains constant unless temperature changes
Q: What happens to equilibrium when temperature increases in an exothermic reaction?
A: It shifts left; K decreases
Q: What happens to equilibrium when temperature increases in an endothermic reaction?
A: It shifts right; K increases
Lab 9 – pH and Buffers
Q: What is the dissociation reaction of a strong acid like HCl?
A: HCl → H⁺ + Cl⁻
Q: What is the dissociation reaction of a weak acid like HA?
A: HA ⇌ H⁺ + A⁻
Q: What is the Ka expression for a weak acid?
A: Ka = [H⁺][A⁻]/[HA]
Q: How do you calculate [H3O⁺] from pH?
A: [H3O⁺] = 10^(-pH)
Q: How do you calculate [OH⁻] from pOH?
A: [OH⁻] = 10^(-pOH)
Q: What is the relation between pH and pOH?
A: pH + pOH = 14
Q: How do you calculate Ka given initial and equilibrium concentrations?
A: Use ICE table and plug values into Ka = [H⁺][A⁻]/[HA]
Q: How do you find equilibrium concentrations from Ka and [HA]initial?
A: Use an ICE table and solve for unknowns
Q: What determines acidity of a salt solution?
A: The nature of the cation and anion (acidic, basic, or neutral)
Q: What are buffer components?
A: A weak acid and its conjugate base (or vice versa)
Q: What buffer has the highest capacity?
A: One with high, equal concentrations of acid and base
Q: How do you calculate pH of a buffer?
A: Use Henderson-Hasselbalch: pH = pKa + log([A⁻]/[HA])
Lab 10 – Equilibria and Thermodynamics
Q: What is the dissolution equation for AgCl?
A: AgCl(s) ⇌ Ag⁺(aq) + Cl⁻(aq)
Q: What is the Ksp expression for AgCl?
A: Ksp = [Ag⁺][Cl⁻]
Q: How do you compare Ksp values?
A: Higher Ksp = more soluble in water
Q: How does temperature affect Ksp in an endothermic process?
A: Ksp increases with temperature
Q: How does temperature affect Ksp in an exothermic process?
A: Ksp decreases with temperature
Q: How do you calculate solubility from Ksp?
A: Set up ICE table and solve using Ksp = x² (or other forms)
Q: What is the common ion effect?
A: Solubility decreases in the presence of a common ion
Q: How do you calculate temperature for spontaneity?
A: T = ΔH° / ΔS°
Q: What is the Gibbs Free Energy equation?
A: ΔG° = ΔH° – TΔS°
Q: When is a reaction spontaneous?
A: When ΔG° < 0