Kinetics
In an elementary bimolecular reaction, how do reactant concentrations affect the rate of the reaction?
The rate remains constant regardless of changes in reactant concentrations.
The rate is directly proportional to the product of the concentrations of two reacting species.
The rate only depends on concentration if a third reactive species is present.
The rate is inversely proportional to the product of concentrations of two reacting species.
Which experimental data would best support a proposed elementary reaction mechanism for a chemical process?
Consistent color change observed throughout all stages of reactant conversion to product.
Unchanged temperature profile despite variations in reactant concentrations.
Constant pressure readings taken during reaction progress under sealed conditions.
Reaction rate changes proportional to concentration changes as predicted by rate laws derived from the mechanism.
If a different step other than the first is the slow step, it's needed to _____ all the reactants up to the slowest step and cancel out any ___________ to determine the rate of the reaction.
Subtract, catalysts
Subtract, intermediates
Add, intermediates
Add, catalysts
What kind of reaction involves three colliding particles, even though it is rare?
Unimolecular
Termolecular
Trimolecular
Bimolecular
Which of the following definitions are correct for an intermediate? (A) Species that are not reactants nor products, (B) formed during the reaction and are consumed by it
A only
B only
Neither A or B
A and B
Comprising two elementary reactions, one being endothermic and the second exothermic, how might the overall ΔH sign differ depending on whether these occur consecutively versus simultaneously?
The overall ΔH tends towards negativity, averaging the opposing heats between the steps.
The overall ΔH always ends up exactly neutralizing because the energies are exact opposites.
The overall ΔH always results in a positive sum since the first step absorbs and the second step emits, canceling out for a net gain.
Overall ΔH may either be positive or negative based on the comparative magnitudes of each step's individual ΔH, irrespective of whether they occur sequentially or simultaneously.
Which condition is not a requirement for a reaction to be spontaneous at all temperatures?
Negative enthalpy change (-ΔH) and positive entropy change (ΔS)
ΔG_system < 0 regardless of ΔH and ΔS values
ΔS_system > 0 and ΔH_system < 0
ΔS_universe > 0 and ΔG_system = 0

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Which of the following are examples of elementary reactions?
Ionization of gas
Decomposition of ozone
Reaction of hydrogen and oxygen to form water
All of the above
The following mechanism is executed: (Step 1: H2O2 + I^- → IO^- + H2O) (Step 2: H2O2 + IO^- → H2O + O2 + I^-). Which statement is true about the overall reaction and rate law?
Overall Reaction: H2O2 → H2O + O2 + I^-, Rate Law: (elementary step 2) rate = k[H2O2]^2[IO^-]
Overall Reaction: 2H2O2 → 2H2O + O2, Rate Law: (elementary step 1) rate = k[H2O2][I^-]
Overall Reaction: 2H2O2 + I^- → 2H2O + O2 + I^-, Rate Law: (elementary step 2) rate = k[H2O2][IO^-]
Overall Reaction: 2H2O2 → 2H2O + O2, Rate Law: (elementary step 1) rate = k[H2O2]^2
A solution's solubility is often influenced by different types of intermolecular interactions; considering this effect, what might you infer about a solute that shows increased solubility when dissolved in polar solvents compared to nonpolar solvents?
The solute likely contains polar or charged functional groups capable of strong dipole-dipole or ion-dipole interactions
It indicates that solute-solute interactions overcome solvent-solvent and solvent-solute interaction strengths
The increased solubility implies a large molar mass leading primarily to enhanced London dispersion force-based dissolution
It suggests that the molecule exhibits significant pi-pi stacking interactions favoring nonpolar environments