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  • Kansas Legislator Proposes Bill to Outlaw Sustainability Education
    A bill has been introduced in the Kansas legislature this week that would prohibit the promotion of ...Read more

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    Kansas Legislator Proposes Bill to Outlaw Sustainability Education

    A bill has been introduced in the Kansas legislature this week that would prohibit the promotion of sustainability. Here is a link to the one-page bill: http://www.kslegislature.org/li/b2013_14/measures/documents/hb2366_00_0000.pdf. See report on Bloomberg News.
  • Earth's Center Is 1,000 Degrees Hotter Than Previously Thought, Synchrotron X-Ray Experiment Shows
    Scientists have determined the temperature near the Earth’s center to be 6000 degrees Celsius, 1000 ...Read more

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    Earth's Center Is 1,000 Degrees Hotter Than Previously Thought, Synchrotron X-Ray Experiment Shows

    Scientists have determined the temperature near the Earth’s center to be 6000 degrees Celsius, 1000 degrees hotter than in a previous experiment run 20 years ago. These measurements confirm geophysical models that the temperature difference between the solid core and the mantle above, must be at least 1500 degrees to explain why the Earth has a magnetic field. For more information about this study, see the press release from the European Synchrotron Radiation Facility.
  • Ocean Volcanic Rocks Contain Samples of Recycled Crust
    Scientists have long believed that lava erupted from certain oceanic volcanoes contains materials fr...Read more

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    Ocean Volcanic Rocks Contain Samples of Recycled Crust

    Scientists have long believed that lava erupted from certain oceanic volcanoes contains materials from the early Earth’s crust. But decisive evidence for this phenomenon has proven elusive. New research from a team including Carnegie’s Erik Hauri demonstrates that oceanic volcanic rocks contain samples of recycled crust dating back to the Archean era 2.5 billion years ago. Their work is published in Nature. Oceanic crust sinks into the Earth’s mantle at so-called subduction zones, where two plates come together. Much of what happens to the crust during this journey is unknown. Model-dependent studies for how long subducted material can exist in the mantle are uncertain and evidence of very old crust returning to Earth’s surface via upwellings of magma has not been found until now. For more information about these results, see the press release from the Carnegie Institution.
This image illustrates the four common states of matter: solid, liquid, gas, and plasma.
General Atomics

States of Matter

This figure shows the four common states of matter: solid, liquid, gas, and plasma.

Consider water as an example. Solid water is ice. Liquid water is, well, water. We call water in its gaseous form "water vapor". A plasma created from water would include electrons, protons (hydrogen atom nuclei), and oxygen atom nuclei (protons and neutrons).

There are special names for most transitions from one state to another. Freezing is turning from a liquid to a solid; melting is turning from a solid to a liquid. The transition from liquid to gas can happen by boiling or evaporation. Condensation is changing from a gas to a liquid. Sometimes (usually at low pressure) a solid can become a gas directly (without first melting to become a liquid); this transformation is called "sublimation". Removing electrons from atoms (usually in a gas) to produce a plasma is called "ionization".

Stars are made of plasma, so plasma is the most abundant form of matter in the universe.

There are several other very exotic and unusual forms of matter that we don't encounter in daily life. A Bose-Einstein condensate can only form at temperature near absolute zero, and was first created in a lab in 1995. Degenerate matter can come into being under incredibly high pressure inside white dwarf and neutron stars. There are other very strange, very rare forms of matter as well.

Last modified June 25, 2008 by Randy Russell.

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Solid is one of the four common states of matter. The three others are gas, liquid, and plasma. There are also some other exotic states of matter that have been discovered in recent years. Unlike liquids...more

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Plasma is known as the fourth state of matter (the first three states being solid, liquid and gas).Matter in ordinary conditions on Earth has electrons that orbit around the atomic nucleus. The electrons...more

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