The periodic table is a well-organized chart that contains all the known elements in the universe. These elements are ...

Now, each element has a chemical symbol made of one or ... that follow will be lower case letters, for example, helium is He. Some element symbols are simple. For example, oxygen is O.Others ...

The lightest element, hydrogen, has an atomic weight of 1.0078. The helium atom, next lightest in the table of elements, weighs 4.002. Are there no substances in between, with atomic weights of ...

And generations of children have sung the words, "hydrogen and helium, lithium, beryllium..." in an attempt to memorise some of the 118 elements. This year, the periodic table of chemical elements ...