Portrait of a Chemist: Mario J. Molina – Formation and Decomposition of Ozone

OpenStax Chemistry 2e The 1995 Nobel Prize in Chemistry was shared by Paul J. Crutzen, Mario J. Molina, and F. Sherwood Rowland “for their work in atmospheric chemistry, particularly concerning the formation and decomposition of ozone.” Molina, a Mexican citizen, carried out the majority of his work at the Massachusetts Institute of Technology (MIT). (a) … Continue reading Portrait of a Chemist: Mario J. Molina – Formation and Decomposition of Ozone

Image: T2 Bacteriophages Attacking E. coli [Colorized TEM] by Lee D. Simon

Lee. D. Simon Coloured transmission electron micrograph (TEM) of T2 bacteriophage viruses (orange) attacking an Escherichia coli bacterium. Each phage consists of a large DNA-containing head and a tail composed of a central sheath with several fibres. The fibres attach to the host cell surface, and the phage DNA is injected into the cell through … Continue reading Image: T2 Bacteriophages Attacking E. coli [Colorized TEM] by Lee D. Simon

Relating Reaction Mechanisms to Rate Laws

OpenStax Chemistry 2e It’s often the case that one step in a multistep reaction mechanism is significantly slower than the others. Because a reaction cannot proceed faster than its slowest step, this step will limit the rate at which the overall reaction occurs. The slowest step is therefore called the rate-limiting step (or rate-determining step) … Continue reading Relating Reaction Mechanisms to Rate Laws

Termolecular Elementary Reactions

Photo by Pixabay on Pexels.com OpenStax Chemistry 2e An elementary termolecular reaction involves the simultaneous collision of three atoms, molecules, or ions. Termolecular elementary reactions are uncommon because the probability of three particles colliding simultaneously is less than one one-thousandth of the probability of two particles colliding. There are, however, a few established termolecular elementary … Continue reading Termolecular Elementary Reactions

Activation Energy and the Arrhenius Equation

OpenStax Chemistry 2e The minimum energy necessary to form a product during a collision between reactants is called the activation energy (Ea). How this energy compares to the kinetic energy provided by colliding reactant molecules is a primary factor affecting the rate of a chemical reaction. If the activation energy is much larger than the … Continue reading Activation Energy and the Arrhenius Equation