Chemical Bonds Ionic and Covalent Bonding

Chemical Bonds – Ionic: Metals + Nonmetals – Covalent: Nonmetals + Nonmetals Sharing of electrons Mostly gases, some liquids and amorphous solids – Metallic: Metal atoms bonded to several other metal atoms

Ionic Compounds *

Properties of Ionic Compounds At room temperature, most are cystalline solids Very attractive forces

Ionic Compounds (Salts): Composed of a Metal ion (cation, M + ) combined with an Non- Metal ion (anion, N - ); atoms exchange transfer electrons. Are Crystalline Solids.CrystallineSolids Have high melting points Smallest component particle is called a formula unit, not a molecule. Cations Anions

Types of Ions Monoatomic ion has only one atom examples are chloride, Cl -, fluoride, F -, sodium Na + Polyatomic ion has more than one, ex. sulfate (SO 4 2- ), nitrate (NO 3 - )

What is the octet rule??? Octet Rule says that atoms tend to gain, lose or share electrons so as to have eight electrons in their outer electron shell

Composed of a Non-Metal combined with another Non-Metal. Are mostly gases, liquids, and sometimes amorphous solids. Have low melting points Bonded atoms share electrons. Covalent (Molecular) Compounds: *

Covalent Bonding Equal & Unequal sharing of electrons: Electronegativity, Polarity and Miscibility Representation of covalent bonding using Lewis Structures Energetics

Polar vs. Non-Polar Polar: – A type of covalent bond in which the electrons are NOT shared equally. – When atoms of different electronegativities form a bond, the electrons tend to be more controlled by the atom with the higher electronegativity.

Non-Polar A non-polar bond is one in which the electrons are shared equally. Covalent bond that has no positive or negative 'ends'.

What are single, double, and triple bonds?? ONLY refers to covalent bonds A single bond is a bond in which two atoms share a pair of electrons. A double bond is a bond that involves two shared pairs of electrons. A triple bond is a bond that involves three shared pairs of electrons

Bonding Theories (1) Valence Shell Electron Pair Repulsion (VSEPR) Theory: considers only the valence electrons and their geometry when they repel each other when they form bonds.(VSEPR) Theory “The best arrangement of a given number of electron domains is the one that minimizes the repulsions among them.”

VSEPR Theory Based on Lewis structures we can know the shape or “geometry” of molecules VSEPR (pronounced “vesper”) stands for Valence Shell Electron Pair Repulsion Electrons around the central nucleus repel each other. Thus, resulting structures have atoms maximally spread out