A little water helps expose the sodium so it can react with the chlorine gas. The reaction releases a lot of heat as the ionic compound sodium chloride is formed. A sodium and chlorine atom are near ...

The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic ...

Elements bond in fixed ratios and so can be represented by a chemical formula. For example, sodium chloride has the same number of sodium ions and chloride ions, so its formula is NaCl ...

One leading theory on the origins of life on Earth proposes that simple chemical molecules gradually became more complex, ...