Elements and Compounds
Chemists have isolated and characterized about 9 million pure substances. A small number of them, exactly 117, are different from all the others. They are the elements. All the rest of the left, are compounds. What distinguishes one element from the compound?
Chemical element is a pure and simple substance that different methods of physical and chemical properties can be dissolved in another substance clean with new chemical compounds. Until now there are 117 known chemical elemcnte. At normal temperatures and pressure 11 elements are gases (Hz, O2, N2, F2, C12, He, Ar, Kr, Xe and Ra), 2 are liquids (bromine and mercure), while others are solid substances.
