Which metal cation is the best oxidizing agent?
a. Pb2+ b. Cr3+ c. Fe2+ d. Sn2+
9.25 Interesting trend in ozone: seasonal variations in polar stratospheric ozone concentration o Southern hemisphere has spring season, longer days o South pole experiences longer days in the spring/summer, which results in more light o Polar stratospheric clouds (PSC) which consist of ice crystals that still catalyze HCl (which is broken down by water) 1. HCl and ClONO 2collect in PSC 2. Two molecules react on PSC for form Cl 2 and HNO 3 3. Cl 2 is photolyzed by visible light and begins the catalytic decomposition of ozone Production of CFC is banned, stockpile exists Until 2010, small amounts were allowed to be produced CFCs are very long-lived and exists in large quantities still today Substitutes for CFCs (trying to cut back on the chlorine molecule by adding hydrogen) o Short term substitution: Hydrochlorofluorocarbons (HCFCs) Hydrogen replaces one chlorine o Longer term substitution: Hydrofluoroolefins (HFOs) Two hydrogen substitutes and no chlorine Global Warming + Climate Change o Matter and radiation: Jean Baptise was the first one to introduce the concept of gases trapping the energy of the sun (greenhouse effect) Tyndall demonstrated experimentally that CO 2 and H 2O ab