Big Idea:The atom is made of a nucleus comprised of protons and neutrons, and an electron cloud found outside of the nucleus. Atomic mass and Avogadro's number can be used to figure out how many atoms are in sample.
Big Idea:Atoms need to balance protons and neutrons in order to be stable. They are considered neutral when the number of protons and electrons are equal, but charge changes when electrons are gained or lost.
Big Idea:Electrons give off energy in the visible light spectrum when they go from an excited state to a ground state. This can be demonstrated with a flame test. Different elements have different flame test colors.
Big Idea:An atomâs electron configuration can be determined by knowing how many electrons are in the atom, and the order of electron filling. Valence electrons play a critical role in chemical bonding and can be represented with Lewis dots.
Big Idea:Atoms become ions by gaining or losing electrons. Atoms become positively charged when they lose electrons and they become positively charged when they gain electrons. Whether an atom is likely to become positive or negative depends on its valence electron