Kinetics
Which factor does not affect the rate of a chemical reaction?
Presence of a catalyst
Concentration of reactants
Color of reactants
Temperature at which reaction occurs
Why does the coefficients matter for elementary steps?
It works for both one-step mechanisms and multi-step mechanisms
None of the above
It needs experimental data
It can be used for the slow elementary step to write rate laws
How can you increase concentration when it's always necessary for your answer?
Add inert gas
Remove some solvent
Increase quantity each component
Reduce size container
In a chemical reaction mechanism, what term describes the step with the slowest rate?
Endothermic step
Exothermic step
Intermediate step
Rate-determining step
Why does NaCl have a lower vapor pressure at room temperature than I2 despite stronger intermolecular forces between Na+ and Cl- ions compared to I2 molecules?
The polar nature of NaCl reduces its tendency to vaporize.
The larger molar mass of I2 increases its vapor pressure.
Covalent bonds within I2 provide greater volatility.
The strong ionic bonds in NaCl require more energy to break into gas phase than London dispersion forces in I2.
For a given reaction with rate law Rate = k[A][B]^2, what would happen to the rate if the concentration of A is halved and B is tripled?
The rate would decrease by a factor of 4.5.
The rate would double.
The rate would increase by a factor of 4.5.
The rate would remain unchanged.
In a proposed mechanism, what role does an intermediate play compared to a transition state?
Transition states occur at every mechanistic step whereas intermediates only form during reversible steps of mechanisms.
Intermediates increase overall energy barriers while transition states serve as temporary stable structures within reactions.
Both intermediates and transition states can be isolated under appropriate conditions if done quickly enough due to their stability levels being comparable.
An intermediate represents an actual chemical species that exists momentarily, while a transition state symbolizes an energetic peak between reactants and products.

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A mechanism is shown below: [Step 1: 2NO(g) ⇄ N2O2(g) (fast)] [Step 2: N2O2(g) + H2(g) → N2O(g) + H2O(g) (slow)] [Step 3: N2O(g) + H2(g) → N2(g) + H2O(g) (fast)] Which of the following is an intermediate?
N2
2NO
H2
N2O2
Which type of solid will CaCl2 form based on its chemical formula and the properties of its constituent elements?
Covalent network solid
Molecular solid
Ionic solid
Metallic solid
In a first-order reaction where concentration doubles over time, what happens to its half-life?
The half-life halves as well since doubling concentration implies twice as much reacting substance every given period.
The half-life increases fourfold as it’s directly proportional to initial concentration squared for first-order kinetics systems.
The half-life doubles because each successive concentration requires double time to reduce by half due to exponential decay nature of first-order kinetics.
The half-life remains constant because it does not depend on initial concentration for first-order reactions.