sOmeone wrote:Were_Fan wrote:A few, such as CO2, don't usually have a liquid phase (think CO2->dry ice evaporating).
Not true, Carbon Dioxide has a liquid phase. You have to take Carbon Dioxide gas, then compress it, at the same time removing the heat from the compression.
http://en.wikipedia.org/wiki/CO2
Please note that I mentioned "usually". Perhaps I should have been more specific. Think of "usually" as as out in the open where we all live our lives, not compressed in a tank. Out in the open, you can watch solid CO2 "dry ice" simply "evaporate" into a mist then disappear. If you cool CO2 without compressing, the gas changes directly to a solid. Out in the open, you can even see trucks transporting liquid CO2 in pressurized tyankers. So, yes, CO2 does have a liquid state but as I said, it is unusual.
Want to see something "unusual" for water? Wait until the temperature is below zero F. Heat some water in a microwave or on the stove until it is over 200F. The temp is not critical and sometimes hot tap water is hot enough but this doesn't work with cold water. Take a coffee cup of that hot water outside and throw it into the air. Instant snow! The liquid water transforms into solid ice while making a "rushing" sound.
Something else unusual for water is that it CAN burn in a manner of speaking. VERY hot fires disassociate the hydrogen and oxygen. The gases then recombine at some point burning the hydrogen. This was a real problem with a coal mine fire several years ago. Can also happen with burning magnesium.
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Jim