Modern Chemistry
Chapter 8: Water Chemistry
When water freezes, energy is released. Conversely, energy is required to melt water by breaking the hydrogen bonds that hold water molecules in a crystalline structure known as ice. Duration: 9:22.
Like most materials, when water is heated it will expand. However, water has another unique property of occupying more space when it melts. Consequently, water is the most dense at 4 degrees Celsius. Duration: 9:17.
Another property of a material is how long it takes to heat up and cool down. This is spelled out in a concept known as Specific Heat. It takes a long time to heat up water, and once it is hot, it takes a long time to cool it down. Duration: 7:52.
A paper cup filled with water is heated with a torch, but does not burn. The energy from the torch is soaked up by the water, which has a high capacity to hold heat. Water's high specific heat has pronounced effects on our global environment. Duration: 6:08.
Watch these additional videos to complete this tutorial.