Metals, Non-metals, and Metalloids

Metals vs. Non-metals vs. Metalloids

• Metals are shiny, dense, and solid at room temperature.
• Metals are good conductors of heat and electricity.
• Metals are malleable and ductile.
• Metals generally have high melting points and readily lose electrons.
• Non-metals are dull, brittle, and poor conductors of heat and electricity.
• Metalloids have properties intermediate between metals and non-metals.

Periodic Table

• The Periodic Table classifies elements by atomic number and groups elements with similar properties.
• Metals are on the left and bottom (except Mercury).
• Non-metals are on the right and top (except Boron).
• Metalloids are between metals and non-metals, forming a "zig-zag" pattern.
• Chemical families include Alkali metals, Alkali Earth metals, Halogens, and Noble gases.

Key Definitions

• Monatomic: An element existing as single, uncombined atoms.
• Diatomic: An element existing as two of the same atoms bonded together.
• Atomic number: The number of protons in an atom's nucleus.
• Mass number: The number of protons plus neutrons in an atom's nucleus.
• Ion: An atom or group of atoms with a positive or negative charge due to an imbalance of protons and electrons.
• Ionic bonding: The attraction of positive and negative ions in a lattice structure.

Electronic Configuration

• Electrons are arranged in shells around the nucleus.
• Electronic configuration determines an element's position on the Periodic Table.
• The number of occupied electron shells indicates the period number.
• The number of valence electrons indicates the group number.

Ion Formation and Noble Gases

• Noble gases have a stable electronic configuration, making them chemically unreactive.
• Group I elements lose a valence electron to form positively charged ions (e.g., K+).
• Group VII elements gain an electron to form negatively charged ions (e.g., Cl-).
• Metals and non-metals react to form ionic compounds.
• Electrons are transferred from the metal atom to the non-metal atom, creating positive and negative ions that attract each other.

Ionic Compounds

• An ionic formula is determined by considering the charges of the ions involved.
• Valency must be stated for ionic compounds containing transition metal ions using Roman numerals (e.g., lead (II) sulphate PbSO4, copper (II) hydroxide Cu(OH)2).
• Non-metal atoms share electrons to achieve a stable arrangement, forming covalent bonds.
• Non-metals form covalent compounds and nearly always exist as molecules (e.g. Chlorine Cl2)

Formulas and Chemical Reactions

• A chemical reaction creates a new substance and is usually difficult to reverse
• Important polyatomic ions to memorize: NH4+, CO32-, OH-, NO3-, SO42-

Chemical Equations

• Steps for balancing chemical equations involving ionic compounds and molecules should be followed excluding state

Solutions and Precipitation

• A solution is a homogenous mixture of two or more substances
• Precipitation occurs when two aqueous solutions of soluble salts mix to produce an insoluble salt precipitate.
• Precipitation happens when ions in solution combine to form a compound with low water solubility, forming solid particles called a precipitate.
• Predicting precipitate formation requires knowledge of substance solubilities.

Naming Ionic Compounds

• Monatomic anions are named with the suffix "-ide”.
• Polyatomic ions are anions generally ending in "ate" (usually an extra oxygen ion) or "ite" (usually one oxygen ion less).