Kinetics
In a chemical reaction mechanism, what term describes the step with the slowest rate?
Endothermic step
Exothermic step
Intermediate step
Rate-determining step
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
Elementary steps are characterized by which of the following?
Number of molecules colliding in that step
How slow or fast the step is
How many reactants are present
How many products are formed
What does the exponent m in the rate law expression Rate = k[A]^m[B]^n indicate about reactant A?
Molar mass of A
Concentration of A
Order with respect to A
Activation energy of A
Which of the following forces is the weakest intermolecular force?
Ionic bonding
Hydrogen bonding
London dispersion forces
Dipole-dipole interactions
The value of the rate constant will ___________ as the temperature increases.
Increase
Multiply
Remain the same
Decrease
What constitutes the rate-determining step within a chemical mechanism?
It's the most energy-consuming step of a mechanism.
It's the slowest step of a mechanism.
It refers to intermediates involved in multiple steps.
It's the fastest step of a mechanism.

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Which term in the rate law equation represents how quickly a reactant is being consumed or a product is being formed?
Reaction order
Rate
Activation energy
Equilibrium constant
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.
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