Honors Chemistry - Chapters 4 & 5

Group (Family)

Vertical column in the periodic table; elements share similar properties and valence electrons.

Period

Horizontal row; properties change gradually across it.

Alkali Metals

Group 1; very reactive metals.

Alkaline Earth Metals

Group 2; reactive metals, less than Group 1.

Transition Metals

Groups 3-12; variable oxidation states, good conductors.

Halogens

Group 17; highly reactive nonmetals.

Noble Gases

Group 18; inert and stable due to full valence shells.

Lanthanides

Rare-earth metals in the top f-block row.

Actinides

Radioactive elements in the bottom f-block row.

Proton

Positively charged particle; defines the element.

Electron

Negatively charged particle orbiting the nucleus.

Neutron

Neutral particle in the nucleus.

Ion

Atom with a charge from losing/gaining electrons.

Cation

Positively charged ion (lost electrons).

Anion

Negatively charged ion (gained electrons).

Ionic Bond

Transfer of electrons between metal and nonmetal.

Covalent Bond

Sharing of electrons between nonmetals.

Metallic Bond

Shared "sea" of electrons among metals.

Polyatomic Ion

Group of atoms acting as a single ion.

Endothermic

Absorbs heat from surroundings.

Exothermic

Releases heat to surroundings.

Calorimeter

Device to measure heat changes in reactions.

Specific Heat (c)

Amount of heat needed to raise 1 g of substance by 1°C.

q = m x c x ΔT

Formula for calculating heat energy.

Absolute Zero

Temperature (0 K) where molecular motion stops.

Thermal Equilibrium

When two objects reach the same temperature.

Evaporation

Liquid → gas; absorbs heat, cools surroundings.

Condensation

Gas → liquid; releases heat.

Conductor

Transfers heat easily (e.g., metal).

Insulator

Prevents heat transfer (e.g., air, glass, vacuum).