Scientific American
Scientific American: What Is an Exothermic Reaction
Scientific American magazine, in the person of Dr. Gerald R. Van Hecke, gives a wonderfully complete answer to this question. Complete with very many hot words for additional background. And a wonderful NASA launch photo.
Science Buddies
Science Buddies: What's the Point of Boiling?
You know that water can exist in three separate phases: solid (ice), liquid (water), and vapor (steam). To change from one phase to another, you simply add (or remove) heat. When water boils, what happens to molecules (for example sugar...
TeachEngineering
Teach Engineering: How Cold Can You Go?
Students explore materials engineering by modifying the material properties of water. Specifically, they use salt to lower the freezing point of water and test it by making ice cream. Using either a simple thermometer or a mechatronic...
TeachEngineering
Teach Engineering: Natural Disasters
Students are introduced to our planet's structure and its dynamic system of natural forces through an examination of the natural hazards of earthquakes, volcanoes, landslides, tsunamis, floods and tornados, as well as avalanches, fires,...
Other
Science Alive: Melting Point Simulation
Percy Julian and Josef Pikl used the fact that melting point-the temperature at which a substance changes from a solid to a liquid-is a characteristic property of a substance to prove that the British chemist Robert Robinson could not...