W2-Kinetics I

10 Questions

Which term defines 'how fast' a process occurs?

Kinetics

What does thermodynamics tell you?

Whether a process will ever happen and 'how much'

What does the integrated rate law provide?

Information about the concentration of reactants over time

What is the focus of kinetics in pharmacy and pharmaceutical sciences?

Stability / shelf life of medicines and decomposition of drugs

What does knowledge of rates of reaction help determine in pharmacy and pharmaceutical sciences?

Duration of action and toxicity of drugs

What is the integrated rate law for a first-order reaction?

$[A] = [A]_0 * e^{-kt}$

What does the rate constant, k, relate to in a reaction?

Reactant concentrations and temperature

In what units are the concentration of a reactant or product typically measured?

Molarity (M)

What type of plot can be used to determine if a reaction is first order?

Natural logarithm of the concentration of a reactant versus time

What does stoichiometry study in a chemical reaction?

Quantitative relationships between reactants and products

Study Notes

In Cooley, Ireland, limestone rocks are being dissolved very slowly.
Solubility of a substance is the maximum amount of it that can dissolve in a given solvent at a specific temperature to reach chemical equilibrium.
Kinetics is the scientific study of the rates and the processes that change chemical compositions and physical properties of a system over time.
The rate of a reaction is the change in concentration of reactants or appearance of products per unit time.
Stoichiometry is the study of the quantitative relationships between the reactants and products in a chemical reaction.
The rate of a reaction is proportional to the molar concentrations of the reactants raised to a power, known as the reaction order.
A reaction's rate constant, k, is a constant that relates the rate of reaction to the reactant concentrations and temperature, and can only be determined experimentally.
For a reaction A + B → P, the rate law is rate = k[A]^n[B]^m, where n and m are the reaction orders of A and B, respectively.
Determining the reaction orders and overall order of a reaction involves analyzing the rates of reactant consumption and product formation.
The units for the rate constant, k, are typically molarity per liter per second (M/L/s).
For a zero-order reaction, the rate of reaction is not dependent on the concentrations of the reactants.
For a first-order reaction, the rate of reaction is directly proportional to the concentration of one reactant.
For a second-order reaction, the rate of reaction is proportional to the square of the concentration of one reactant or the product of the concentrations of two reactants.
Integrated rate laws are the solutions to the differential rate equations and can be used to find the concentrations of reactants or products at specific times.
A plot of the natural logarithm of the concentration of a reactant versus time can be used to determine if a reaction is first order.
A plot of the concentration of a reactant versus time can be used to determine if a reaction is zero order.
The units for the concentration of a reactant or product are typically molarity (M).
The initial concentration of a reactant, [A]0, can be determined from the intercept of a plot of the natural logarithm of the concentration versus time for a first-order reaction.
The concentration of a reactant, [A], after a certain time can be estimated from the slope of a plot of the natural logarithm of the concentration versus time for a first-order reaction.
The integrated rate law for a first-order reaction is given by [A] = [A]0 * exp(-kt).
The integrated rate law for a zero-order reaction is given by [A] = [A]0 - kt.