Chemical reactions occur when elements or compounds combine and create new compounds. Elements are substances that contain only one type of atom and are represented by unique symbols on the periodic ...

Everything we can see and touch, and quite a lot that we can’t as well, is made of tiny particles called atoms. Some substances, like particles of this iron, contain only one kind of atom. Iron is an ...

Atoms are the building blocks of everything. Atoms can form strong bonds with each other, making molecules. Symbols and formulae Letters from the alphabet are used to represent chemical elements. An ...