Chapter 2: Chemical Units and Their Identities
Subject:
Chemistry [1]
ATOMS: - made of nucleus (protons (positive charge) and neutrons (neutral charge)) and electron cloud (electrons (negative charge) - smallest particle that still retains properties of element - atomic # - # of protons (unique to each element) (also # of electrons in neutral atoms) - mass # - # of protons + neutrons - atomic mass - actual (average) mass of atom (measured in daltons) - about mass # b/c electrons have very small mass compared to protons/neutrons - isotope - atom w/ more/less than usual # of neutrons ELECTRONS: - elemental form of element is when element is by itself - compound - joint of 2+ elements w/ own set of properties diff. from elements - elements in periodic table are arranged in atomic # and are in 18 columns (groups)