Need help from an expert?
The world’s top online tutoring provider trusted by students, parents, and schools globally.
The rate law describes the relationship between the rate of a chemical reaction and the concentrations of its reactants. Activation energy is the minimum amount of energy required for a reaction to occur.
One example of a rate law is the reaction between hydrogen peroxide and iodide ions:
2H2O2 + 2I- → 2H2O + I2
The rate law for this reaction is:
Rate = k [H2O2] [I-]
where k is the rate constant and [H2O2] and [I-] are the concentrations of hydrogen peroxide and iodide ions, respectively.
Activation energy can be determined experimentally by measuring the rate of a reaction at different temperatures and using the Arrhenius equation:
k = Ae^(-Ea/RT)
where k is the rate constant, A is the pre-exponential factor, Ea is the activation energy, R is the gas constant, and T is the temperature in Kelvin.
By plotting ln(k) against 1/T, the activation energy can be calculated from the slope of the line. A higher activation energy means that the reaction requires more energy to occur and will therefore have a slower rate.
Understanding rate laws and activation energy is important in predicting and controlling chemical reactions, as well as in the development of new drugs and materials.
Study and Practice for Free
Trusted by 100,000+ Students Worldwide
Achieve Top Grades in your Exams with our Free Resources.
Practice Questions, Study Notes, and Past Exam Papers for all Subjects!
The world’s top online tutoring provider trusted by students, parents, and schools globally.