Roger Black, age 10, of Sioux Falls,

What is the earth made of?

The world and everything in it is made of little bitsy things called atoms. They are too small to be seen, even through the most powerful lens. Two billion of them could sit on the period at the end of this sentence, Though atoms are usually too busy to sit still anywhere,

In nature there are only 109 different kinds of atoms„ Variations of moss kinds have been discovered. The scientists have made a few new ones. Of course there are far mere than 109 different materials in the world to make them, the atoms act very much like your building blocks,

You can use two long blocks and a half‑circle to make an archs Two atoms of hydrogen and one atom of oxygen  team up to make a molecule of water. Some materials use three or four different kinds of atoms. Imagine all the different combinations of this sort that 109 atoms could work out. They build together to make wood, ice cream, glass, clothes, hairs fingernails and a million other different materials.

Each of the 109 atoms is different from all the rest. But each and every one is made of still tinier electric particles. These particles are not all alike. Those called protons are made of positive electricity. Those called electrons are made of negative electricity, There are other atom particles too. But every healthy atom has an equal number of protons and electrons,

The difference between the atoms is that some have more of these particles than others. Those with more are bigger and weigh more. The smallest atom possible is an atom of the gas hydrogen, It has but one proton and one electron. An atom of uranium is a big one, as atoms go. It has 92 protons and 92 electrons besides other particles.

Experts have listed the different atoms by the number of their proton particles. Hydrogen with but one proton heads the list as atom number to Gold with 79 protons is atom 79, silver is 47, carbon is 6 and oxygen is 8.

The different atoms fit into a neat table, called the periodic table from 1 to 109 with the heavier man‑made atoms tagged on at the end.

Every atom is very neat; Its protons are wadded together in a core called the nucleus. The electrons are arranged outside in orderly shells. A proton is 1840 times as big as an electron. The nucleus probably haw as much room as a fly in a movie house.

The particles in the nucleus are held very tight. Atomic energy is the force released when we smash the nucleus of atoms apart: The outside electrons however, are always popping like buttons off a coat. They visit with electrons of nearby atoms: In fact, that is how they often bundle up to make a new substance. The spritely electrons may force the rest of their atoms to follow them. Before you know it two kinds of atoms have teamed up to make a substance different from either of them.