1. Basic Characteristics of Substances and Elements

Group VI. A

Includes Oxygen, Sulphur, Selenium, Tellurium, Polonium

Noble Gases

Inert; do not normally form compounds with other elements; valence orbitals completely filled with electrons

Alkali Metals

Group 1/I. A; includes Lithium, Sodium, Potassium, Rubidium, Cesium, Francium

Alkaline Earth Metals

Group 2/II. A; includes Beryllium, Magnesium, Calcium, Strontium, Barium, Radium

Halogens

Group 17/VII. A; includes Fluorine, Chlorine, Bromine, Iodine, Astatine

Lanthanides

Series of 15 metallic chemical elements (atomic numbers 57-71)

Chlorine oxidation numbers

Can take on lower oxidation numbers like -1, +1, +3, +5, +7

Orbital

Region of the most probable occurrence of a given electron

Pi (π) bond

Covalent bond formed by sideways overlap of p orbitals

Sigma (σ) bond

Covalent bond formed by direct, head-on overlap of atomic orbitals

s-orbital

Spherical shape; involved in sigma bonds; cannot participate in pi-bond formation

Gases under normal conditions

Fluorine, Chlorine, Radon, Xenon

Radioactive elements

Elements that undergo radioactive decay; e.g., Uranium , Technetium

Stable elements

Elements that do not undergo radioactive decay; e.g., Lead (most isotopes), Lithium , Silver , Carbon

End product of radioactive decay

Lead

Property common to all metals

Good electrical conductivity

Atomic number (Z)

Number of protons in an atom's nucleus

Element with most protons

Nielsbohrium (107 protons)

Electronegativity

Tendency of an atom to attract a bonding pair of electrons

Highest electronegativity

Fluorine

Lowest electronegativity

Cesium

Group with lowest electronegativity

Alkali metals

Elementary particle with largest rest mass

Neutron