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Roxana Conley age 14. of Poteaus,  Okla.

What is absolute zero?

Gabriel Fahrenheit. searched for the coldest thing known. He found it in a mixed brew of ice, salt and water, Fahrenheit needed a scale of degrees for his thermometer.  His new invention was a glass tube attached to a glass bulb.  The bulb and part of the tube were filled with liquid mercury, Fahrenheit dipped the bulb into his icy brew and watched the mercury shrink and fall in the glass tube, He put a mark where it came to rest. That mark he called 0 degrees, That was the zero of Fahrenheit’s first scale of temperature degrees and in 1724 when this happened it was the coldest temperature anyone knew existed.

Since then much has been learned about temperature. Strange to say, the coldest temperature was discovered by studying heat 'the nature of heat was a tough problem. For generations the best brains worked to solve it. Heat we now know, is a form of energy. It is the activity of the minute atoms and molecules of which everything is made,

The molecules of hot, boiling water are rushing around at a great rate. Some of them get up enough speed to tear right off into the air as steam and vapor. As the water cools its molecules slow down to a more leisurely pace, But they still move as there is still heat, or energy in the water.

They are still moving though more slowly when the water is icy cold, And there is still some movement among them when the water is frozen to a solid block of ice for the temperature can go much lower than that of frozen water.  Dry ices for instance may be more than 100 degrees colder than ordinary ice, and there is still some heat energy in dry ice, its molecules are still moving,

Cold then is lack of heat energy. Temperatures drop as the tiny molecules move more and more slowly. And to this slowdown there must be a limit. The limit is reached when every single molecule in a substance has come to an absolute standstill. All the heat energy has gone, The temperature has reached absolute zero,

On the Fahrenheit scale of today this temperature is minus 460 degrees. On the Centigrade scale it is minus 273 degrees, Absolute zero on this scale, is 273 degrees below the freezing point of water. Fahrenheit never dreamed such a temperature was possible. Absolute zero is almost impossible to produce even in our modern laboratories.

At absolute zero there are no gases and no liquids. Air freezes solid long before this temperature is reached, As far as we know nothing can get any colder than minus 273 degrees Centigrade, for all the heat energy has gone and the busy molecules are perfectly still

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