Tiny Wonders / Atom
Tiny Wonders What is an Atom? ATOMS ARE THE VERY SMALL BITS or particles of the thing of which any substance is made. They are too small to be seen. Two billion atoms would fit on the dot that is on the top of this 'i'. Scientists earlier thought atoms were the tiniest things in the universe, like hard balls that could never be split or destroyed. But now, they know that atoms are more like clouds of energy, mostly empty space, containing even tinier sub-atomic' particles. Inside an atom At the center of every atom, there is a dense core or 'nucleus' having two kinds of tiny particles protons and neutrons. Around the nucleus, there are even tinier particles called electrons that move around at the speed of light. Size of atoms Atoms weigh about 100 trillionths of a trillionth of a gram and are about a ten-millionth of a millimeter big. The smallest atoms are the hydrogen atoms. Helium nucleus One of the smallest nuclei of an atom is that of an at...