Suzanne Honsberger, age 11, of Jordan

What are elements?

We are all used to the idea that everything in our world is made of atoms, too small for our eyes to see. For example        an atom of soot, which is carbon, measures about one hundred millionth part of an inch and .there are countless billions of atoms in every thimbleful of ordinary air. There arc; only about 90 different atoms in our everyday world, and the bulk of the earth is made from less than a dozen different varieties. 'when a substance is rude entirely of atoms of one sort, it is a chemical element; The way the elements combine with each other to make the countless different things around use wood anO, wool rocks and rayon, air and water, is the story of chemistry.

The atoms which make up an element are all alike in size and in the way they behave with other atoms. Each element has its own boiling point and its own freezing point. The boiling point of the element oxygen is far below ordinary temperatures which is why we find free oxygen as a gas in the air. The freezing point of the element gold is far below ordinary temperatures, which is why we find pure gold in solid nuggets.

It is not always possible to tell which element is which merely by looking at it. Magnesium looks a lot like silver and a flask of oxygen looks just like a flask of nitrogen. However, each element follows its own rules of chemical behavior, Nitrogen atoms are very stand‑.offish and  combine with  the other elements, Oxygen a tows are quite the reverse, They are always ready to team up with almost any kind of atom.

One of oxygen’s favorite tricks is to team up with atoms of hydrogen. Hydrogen is a highly inflammable gas and oxygen is the gas •.‑Which fuels every fire. Yet together, these two fiery elements form fires greatest enemy ‑ water. At normal temperatures, water is a liquid and its boiling and freezing boiling and freezing points arc different from these of either of its parents. Oxygen also teams up with other elements to make the solid rocks of the earth’s crust.. Almost half of the solid ground on which we live is made from oxygen.  A still more amazing compound is ordinary table salt. It is a compound, of tyro poisonous elements., silvery white sodium metal and chlorine gas.

There is not limit to the number of different compounds Nature can make from a few basic elements. There are only 92 of these chemical elements in our everyday world and science has discovered a few pore by laboratory experiments. Most of them are so rare that we never see or hear of them. The most abundant is oxygen which is present in the airy in water and in most rocks, About nine per cent of the earth’s crust is made from the following elements in combination with one another; oxygen, silicon, aluminum, iron, calcium, sodium and potassium. The: remaining one per cent is shared by the rest of the chemical elements.