Since then, the periodic table has evolved to reflect over 150 years of scientific development and understanding in chemistry and physics. Today, with 118 known elements, it is widely regarded as one ...

When it comes to science, chemistry ... of these elements do you know? Test your knowledge and compete with other Live Science readers to see who can come top in our periodic table quiz.

The colors of rubies and emeralds are so striking that they define shades of red and green—ruby red and emerald green. But ...

The periodic table - AQA Mendeleev made an early periodic table. In the modern periodic table, elements are in order of atomic number in periods and groups. Electronic structures model how ...