CHEM 120B Lecture Notes - Lecture 5: Ozone Layer, Activation Energy, Chlorine

• School: CSUF
• Department: Chemistry and Biochemistry
• Course: CHEM 120B
• Professor: Andrew Petit

Document Summary

The ozone layer protects the earth from ultraviolet light, which is harmful to living organisms. The hole in the ozone layer was caused by humans. Ozone molecule (o3) slam into clo atom. Then clo and oxygen atom make chlorine and oxygen gas. This is contrasted from the two oxygen molecules formed without chlorofluorocarbons. Catalyst: undergoes no net change in concentration: chlorine is the catalyst. This process has a smaller activation energy; the reaction then is faster. The beginning and the end (delta-h) are the same but the different pathway/mechanism lowers the activation energy. Catalysts: stay constant in their concentration: similar to intermediates in that they do not appear in the net chemical equation, however, intermediates always have a small concentration (they are made only to be quickly used up). Stretches the molecule so that it is easier to break down. Homogeneous: catalysts and reactants occur in the same phase.