ASTRON 2B03 Lecture Notes - Lecture 1: Puffy Amiyumi, Praseodymium, Technetium

• School: McMaster University
• Department: Astronomy
• Course: ASTRON 2B03
• Professor: Christine Wilson

Document Summary

The proton has a positive electric charge equal and opposite to the electron, while the neutron has almost the same mass as the proton but no electric charge. The atomic number of an atom is the number of protons or electrons in the atom (the number of protons equals the number of electrons, for an electrically neutral atom). This number determines the type of element it is; each type of element has a different name and behaves in a unique way chemically. The different elements may have familiar names like hydrogen, oxygen, carbon, iron but many have ones that are not so familiar (rhenium, praseodymium, technetium ). The atomic weight of an atom is its total number of protons and neutrons combined. You can change the number of neutrons and still have the same element -- the number of neutrons doesn"t affect the chemical properties of the atom -- but it does of course affect its mass or atomic weight.