Unit 1
Which intermolecular force is present in all molecules?
A. Hydrogen bonding
B. Dipole–dipole forces
C. London dispersion forces
D. Ion–dipole forces
C. London dispersion forces
Which of the following increases reaction rate?
A. Lower temperature
B. Higher activation energy
C. Increasing reactant concentration
D. Removing catalyst
C. Increasing reactant concentration
What is substance that can act as both an acid and a base called?
amphoteric/amphiprotic
Which of the following processes results in an increase in entropy (ΔS > 0)?
A. Freezing water
B. Condensing steam
C. Evaporating alcohol
D. Forming a solid precipitate
C. Evaporating alcohol
What does PLTL stand for
Peer-Led Team Learning
Select ALL substances that can form from hydrogen bonds:
□ H₂O
□ NH₃
□ CH₄
□ HF
H₂O, NH₃, HF
Which are characteristics of a first-order reaction?
□ Rate ∝ [A]¹
□ Units of k: s⁻¹
□ Half-life depends on concentration
□ A plot of ln[A] vs t is linear
Rate ∝ [A]¹, Units of k: s⁻¹, A plot of ln[A] vs t is linear (1,2,4)
Acetic acid is weak because its conjugate base, acetate, is relatively _____ (stable or unstable?)
stable
Which situations typically lead to higher entropy? (Select all that apply.)
A. A gas expands
B. Temperature decreases
C. A solid melts
D. Molecules mix
A. A gas expands
C. A solid melts
D. Molecules mix
What is your course number and section?
CHEM 1312-02P
Which statement best explains why HF has a higher boiling point than HCl?
A. HF has stronger London forces
B. HF has hydrogen bonding
C. HF has a larger molar mass
D. HF is nonpolar
B. HF has hydrogen bonding
For the reaction:
Rate=k[A]2[B]
What happens to the rate if [A]is doubled and [B]is halved?
A. Rate stays the same
B. Rate doubles
C. Rate increases by factor of 4
D. Rate increases by factor of 2
C. Rate increases by factor of 4
What is the pH of a solution with [OH⁻] = 1.0 × 10⁻⁸ M?
6
Complete the sentences:
If G < 0 the reaction is _______, but if G > 0 then the reaction is _______. Lastly, reactions with G = 0 are in ________.
Spontaneous, Nonspontaneous, Equilibrium
WHERE is our office located?
ELCTR 112
Explain how intermolecular forces affect viscosity and vapor pressure of a liquid.
Stronger IMFs → higher viscosity, lower vapor pressure.
Weaker IMFs → lower viscosity, higher vapor pressure.
Describe what an ICE table is used for in equilibrium calculations and outline the steps to solve for equilibrium concentrations using kc.
Identify initial concentrations, assign x changes, write equilibrium expressions, substitute values into kc, solve for x, compute equilibrium concentrations.
Calculate the solubility of SnS in g/L at 25°C, when the Ksp value is 2.34 x 10-7
0.072
A reaction at equilibrium has ΔG = 0, but the reaction still contains both reactants and products. Explain why the reaction does not stop and what ΔG = 0 means in terms of molecular behavior.
Where is the Learning Center?
Next to the library
A compound has a heat of vaporization of 38.0 kJ/mol. Using the Clausius–Clapeyron equation, calculate the vapor pressure at 350 K if the vapor pressure is 150 torr at 310 K.
Hint:
ln(P1/P2) = (Hvap/R) x ((1/T2)-(1/T1))
P2= 390 torr
For the reaction:
2A⇌B
At 700 K, K_c=4.0. If 1.00 mol of A and 0 mol of B are placed in a 2.00 L container, calculate the equilibrium concentrations.
A 0.085 M solution of a weak acid, HA, has a measured pH of 3.19.
Calculate the acid dissociation constant, Ka, for HA.
4.9 x 10-6
For a reaction in which H = 225 kJ/mol and S = 125 J/Kmol, determine the temperature in Celsius above which the reaction is spontaneous.
1527 Co
What are our names?
Emiliano, Juan, and Mary