The Periodic Table shows the elements in order from left to right based on their number of protons. Hydrogen (H) has 1 proton, Helium (He) has 2 and Lithium (Li) has 3. Protons are the positively charged nuclei that make up the majority of the mass of an atom. Atoms also have neutrons that are neutral and equal in number to the protons but smaller. This neutral mass is called the neutron number and is given a symbol of N. Neutrons are a very important part of the mass of an element because they are what holds the atomic nucleus together and gives it its shape.
The 3rd type of sub-atomic particle is the electron and it has a negative electric charge. The electron orbits the nucleus of an atom in a large region of space and makes up the rest of the atomic mass of an element. Atoms of different elements can combine with each other to form chemical compounds that have many useful properties such as plastics, metals and many natural and synthetic substances. Atoms of the same type can be arranged in regular patterns to form solids that are often called crystals. These crystal structures control properties such as strength, ductility, density and conductivity (ability to transmit heat or electricity).
Bohrium is named for its discoverer Niels Bohr, who was awarded the Nobel prize for his work on understanding the structure of the atom. Bohrium is a synthetically produced element that has a very short half-life, only seconds long, and is used mostly for basic research purposes. It is a member of the group 7 elements and acts much like the lighter homologue, rhenium, which appears directly above it in the periodic table.