Geothermal Energy and Mixtures
The past two discussions of physical science have included discussions on energy, specifically heat energy. It was discussed how heat energy can be taken from the sun, and it was also mentioned that there is heat stored in the earth. This heat inside the earth comes from minerals that are reacting at the earth's center. Scientists have learned how to use this heat as an energy source for power or electricity. The electricity derived from the heat in the earth is called geothermal electricity.
Geothermal power is a cleaner form of power compared to fossil fuels. Sometimes geothermal power plants use plain heat or steam that is piped through the earth, or they use heated water like the ones found in geysers. For an yummy kids science project that shows you the power of heat, ask your mother to steam you some Chinese dimsum. The heated water used to make the dimsum, never touches the dimsum itself. Instead, the water gets very hot and gives off heat energy through steam which cooks the dimsum. In the same way, steam from the earth can be channeled to power our homes and keep us warm!
Some places where geothermal power can be harnessed are near volcanoes. This is because the heat of the earth is very hear the surface, and sometimes it forms geysers or hot springs near the volcano, and these can be used for harnessing energy. In the classic kids science project of making a volcano erupt, we can also study how steam around the volcano can be useful to society.
Apart from geothermal energy, the classic kids science project discussed in the former paragraph also teaches us about mixtures. A mixture is when at least two substances are mixed together, but do not combine themselves on a chemical level. The volcano project uses baking soda and vinegar in order to create a chemical reaction in which the liquid bubbles, and seemingly boils over, similar to what seems to happen when a volcano erupts. Some fancier kids science projects have also figured out ways to make steam come out of the volcano first, which usually happens before an actual volcano explodes.
The kids science project on making a volcano is a good example of both geothermal or heat power found in the earth, as well as chemical reactions of substances or mixtures. It is important to understand that baking soda and vinegar have nothing to do with geothermal power, even though geothermal power also is a result of chemical reactions. The minerals found at the earth's surface are very different, and have mixed in different ways in order to produce their power.
