It is an icon of natural science and hangs in most chemistry classrooms: the periodic table of elements, which is celebrating its 150th birthday this year. The tabular overview is closely linked to ...

Learn all about the 118 combinations of protons, neutrons and electrons that make up our world. Whether hung on classroom walls, put up in dorm rooms or screen-printed on T-shirts, the periodic table ...

The periodic table of elements, or Mendeleev’s table, was created in 1869 by Russian chemist Dmitri Mendeleev. This table organizes all known chemical elements by their atomic number, or the number of ...

The high relative abundance of these tellurium isotopes gives tellurium the greater relative atomic mass. The atomic number of tellurium is 52 and the atomic number of iodine is 53, so these elements ...