Answer: arrangement of constituent particles makes glass diff. from quartz. Glass-short range order of particles.
Quartz-Long range of particles.
If quartz is heated and cooled rapidly it can be converted to glass.
white phosphorus is used in flares and explosives, so may be important in warfare, etc. Red phosphorus is used in matches (side of matches) and in fertilizers which are essential to growing plants. I don't know if that is economically important, but there are many ways that phosphorus benifit the economy. One downside on the economy is that phosphorus is one of the main ingredients in meth, which of course causes trouble for the economy ( law enforcement, medical, etc. )
B. (twenty characters blah blah blah) Have a great day/night!
Heat in the mantle comes from the Earth's molten outer core, decay of radioactive elements and, in the upper mantle, friction from descending tectonic plates.The temperature difference between the upper and lower boundaries of the mantle requires heat transfer to occur.
Material heating up in the mantle
