Dianne Kasper, Age 10, Of Bridgeport, Conn., For Her Question:
What are gases?
As we go about our daily lives on the face of the earth we are surrounded by oceans of gases on every side. We cannot see, taste or sme11 these common gases, and unless they are moving we cannot feel them. They are of course, the gases of the air, and we need them to stay alive.
The desert sun may be comfortable and even bracing when the temperature rises as to high as 90 degrees. But in a swampy valley a day as hot as this is likely to be weary and dreary with steamy humidity. The humid discomfort is an extra quota of water gas in the air. Water, like other substances, is made from units of matter called atoms and molecules which are far, far too small for our eyes to see. And these particles of matter can occur in a solid state, a liquid state or a gaseous state depending upon the temperature.
Atoms and molecules are restless units, and heat gives them energy to move around at faster and faster speeds. As they lose heat the tiny particles are forced to slow down. The difference between solid ice, liquid water and gaseous water vapor are no more than the different speeds at which the individual water molecules are
Traveling and this speed energy is the temperature of the watery substance. Molecules of water have/natural attraction for each other which tends to hold them together. When they travel slowly, this attraction binds them together in rigid formation as solid ice. This happens when the temperature drops to 0 degrees centigrade.
When the temperature is between 0 and 100 degrees, the water molecules have enough speed energy to slither and s1ide around each other, stream and flow in the liquid state. But they must stay linked together because they are not yet traveling fast enough to break the natural attraction which binds them.
At 100 degrees centigrade water reaches its boiling point. Its molecules now have enough speed energy to break apart and go their separate ways. The liquid water becomes a gas and mingles with the other gaseous substances in the air. Each substance has a boiling point at which its atoms or molecules get up enough speed to separate and change from the solid or liquid state to the gaseous state. Gold melts to the liquid state at 1063 degrees and becomes a gas at 2600 degrees. Iron becomes a gas at 3000 degrees. Atoms of neon and oxygen, helium and nitrogen get enough energy from normal room temperatures to separate and become gases.
Gas is the most active state of matter, and the separate m01ecules in a cup of water vapor spread out to the farthest walls and corners. They diffuse or pass among the other gases of the air. The assorted gases are somewhat like miniature balloons traveling helter skelter at perhaps 10,000 mi1es an hour. The miniature speeders bump and bounce each other, changing directions some five billion times a second.