Starting with a beaker of ice, the temperature will be measured each 2 minutes for about 20 minutes. After the ice has completely melted, the water will be heated until boiling and vapor production occurs. While that is happening, a florence flask of about 50 ml of water is being heated to boiling. Once boiling has started, the flask is removed from the heat and a rubber stopper is inserted, until the bubbling stops. The stoppered flask is placed under cold running water and the re-starting of boiling noted. A cold watch glass is placed over the boiling beaker of water and condensation noted on the cool bottom. The use of dry ice in coolers, with no formation of water as the ice melts was described, along with the condensation of iodine on a watch glass as iodine crystals are heated to vaporization. The definitions of melting point, boiling point, vaporization, condensation, and sublimation were shown by these demonstrations. Why the water reboiled under the cold water to be discussed at the next class.