Energy & Green Tech

New Zealand's green hydrogen edge

Aotearoa New Zealand is likely to have a competitive advantage when it comes to generating clean, green hydrogen and this edge should help the country reduce its future reliance on fossil fuels, says a leading sustainable ...

Energy & Green Tech

A way to produce hydrogen directly from untreated sea water

A team of engineering and materials scientists from China, Australia and the U.S. has developed a process for using sea water to produce hydrogen without having to first pretreat the water. In their paper published in the ...

Energy & Green Tech

Targeted policies could help decarbonize Canada one home at a time

Be it through the food we eat, vehicle we use or way we live, we use fossil fuels and emit greenhouse gases in various activities in our daily lives. We need to reduce emissions across sectors, starting with our homes. This ...

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Gas is one of the three classical states of matter (the others being liquid and solid). Near absolute zero, a substance exists as a solid. As heat is added to this substance it melts into a liquid at its melting point (see phase change), boils into a gas at its boiling point, and if heated high enough would enter a plasma state in which the electrons are so energized that they leave their parent atoms from within the gas. A pure gas may be made up of individual atoms (e.g. a noble gas or atomic gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or compound molecules made from a variety of atoms (e.g. carbon dioxide). A gas mixture would contain a variety of pure gases much like the air. What distinguishes a gas from liquids and solids is the vast separation of the individual gas particles. This separation usually makes a colorless gas invisible to the human observer. The interaction of gas particles in the presence of electric and gravitational fields are considered negligible as indicated by the constant velocity vectors in the image.

The gaseous state of matter is found between the liquid and plasma states, the latter of which provides the upper temperature boundary for gases. Bounding the lower end of the temperature scale lie degenerative quantum gases which are gaining increased attention these days. High-density atomic gases super cooled to incredibly low temperatures are classified by their statistical behavior as either a Bose gas or a Fermi gas. For a comprehensive listing of these exotic states of matter see list of states of matter.

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