The Periodic Table 6.1 Mendeleev’s Period Table • Set up by atomic mass v. atomic number-modern • Elements in groups have similar properties • Groups: vertical • Periods: horizontal Numbering the Periodic Table Mapping the Periodic Table: Metals, Nonmetals, Metalloids Metal Properties 1. High luster or sheen – reflects light 2. Conducts electricity 3. Conducts heat 4. Ductile (can be drawn into wires) 5. Malleable (can be hammered into sheets - bends) 6 Non metals Properties 1. Dull – no sheen 2. Insulator – doesn’t conduct heat or electricity 3. Brittle – will shatter not hammer into sheets 4. Most are gases at room temperature – P, S, Se, I are solid – Br is liquid 7 Metalloid (semimetal) Properties • Has characteristics of both metals and nonmetals 1. Tend to be semi-conductors (conduct electricity under right conditions. 2. Can be shiny (have a sheen) 3. Can be brittle 8 Extended Periodic Table Group Names, Representative, Transition metals and Inner transition (rare earth) metals Ch. 6.2 and 6.3 • Electron configuration • Ions and charges • Periodic Trends Electron configuration on the Periodic Table Electron config. Blocks Electron configuration using P.T. • e- config of Ca using P.T. • Shortcut using Noble gases Valence electrons • Valence Electrons (v.e.): – electrons used in bonding elements – Electrons in the highest energy level • s and p sublevels – maximum is 8 – Valence electrons is the same as the group number (for representative elements) • Example: Mg is group 2A, has 2 v.e. Valence electrons in P.T. Ions • Atoms gain or lose electrons to obtain a noble gas configuration – Cations: positive charge bc they LOSE electrons. • Ca: loses 2 e- becomes +2 charge to be like Ar (Ca+2) – Anions: negative charge bc they GAIN electrons • Cl: gains 1 e- be come -1 charge to be like Ar (Cl-) Charges of the Ions Ch. 6.3 Definitions • Atomic Size (radius): one half the distance between the nuclei of 2 atoms of the same element when 2 atoms are joined. – Ions: atom (or group of atoms) that has a positive or negative charge by losing or gaining electrons. • Anions: larger than original atom • Cations: smaller than original atom Periodic Table Trends Atomic Radius Vocabulary • Ionization Energy: energy required to remove the first electron from an atom. • Electronegativity: the ability of an atom to attract an electron when an atom is in a compound. (number value assigned arbitrarily 0.7- 4) Periodic Table Trends Increasing electronegativity and ionization energy.