Understanding Metallic and Molecular Bonding

Metallic bonding

Attraction between metal atoms and delocalized electrons.

Delocalized electrons

Electrons that move freely in a metal's orbitals.

Crystal lattice

Regular arrangement of metal atoms in solid state.

Electron sea model

Visualization of mobile electrons around metal atoms.

Electrical conductivity

Ability of metals to conduct electricity efficiently.

Thermal conductivity

Metals' ability to conduct heat effectively.

Malleability

Ability to be hammered into thin sheets.

Ductility

Ability to be drawn into wires.

s-block metals

Metals with one or two valence electrons.

p orbitals

Three outer orbitals in s-block metals, vacant.

d-block metals

Metals with vacant d orbitals below highest energy level.

Metallic luster

Shiny appearance due to light absorption and emission.

Enthalpy of vaporization

Energy required to vaporize a metal, indicates bond strength.

Bond strength

Varies with nuclear charge and electron sea size.

High energy levels

Few electrons occupy the highest energy levels in metals.

Crystal structure of sodium

Sodium atoms surrounded by eight others in a lattice.

Resistance to breaking

Metals can slide past each other without bond breakage.

Light absorption

Metals can absorb various light frequencies.

Re-radiated light

Light emitted after electrons drop to lower energy levels.

Vacant orbitals

Empty orbitals allow electron mobility in metals.

Metallic properties

Characteristics arising from metallic bonding and electron mobility.

Strong absorbers

Metals can absorb a wide range of frequencies.

Fixed position of atoms

Atoms in metals are relatively stationary in lattice.

Enthalpy of Vaporization

Energy absorbed during vaporization at constant pressure.

Electron-Sea Model

Describes metallic bonding with delocalized electrons.

Metallic Bond Strength

Stronger bonds correlate with higher enthalpy of vaporization.

Malleability

Ability of metals to be shaped without breaking.

Ductility

Ability of metals to be drawn into wires.

Ionic Crystals

Brittle structures due to strong ionic bonds.

Electrical Conductivity

Metals conduct electricity due to free-moving electrons.

VSEPR Theory

Predicts molecular geometry based on electron repulsion.

Molecular Polarity

Uneven charge distribution in molecules affects interactions.

Hybrid Orbitals

Formed by combining multiple atomic orbitals.

Bond Angles

Angles between bonds in a molecule determined by geometry.

Linear Molecules

Molecules with atoms arranged in a straight line.

Diatomic Molecules

Molecules consisting of two atoms, e.g., H2, HCl.

Covalent Bond

Chemical bond formed by sharing electron pairs.

Octet Rule

Atoms tend to form bonds to achieve eight electrons.

Weak Intermolecular Forces

Forces between molecules affecting physical properties.

Hydrogen Bonding

Strong dipole-dipole attraction involving hydrogen atoms.

London Dispersion Forces

Weak forces due to temporary dipoles in molecules.

Dipole

Molecule with positive and negative ends due to polarity.

Chemical Formula

Symbolic representation of a compound's composition.

Molecular Geometry

Three-dimensional arrangement of atoms in a molecule.

Valence Electrons

Electrons in the outer shell involved in bonding.

Molecular Shape

Determined by the arrangement of bonded atoms.

Hydrogen

A diatomic molecule represented as H2.

Hydrogen Chloride

A diatomic molecule represented as HCl.

Boron Trifluoride

An AB3 molecule with trigonal-planar geometry.

Methane

An AB4 molecule with tetrahedral geometry.

Beryllium Fluoride

An AB2 molecule with linear geometry.

VSEPR Theory

Predicts molecular shapes based on electron pairs.

AB2 Molecule

Linear geometry with 180° bond angles.

AB3 Molecule

Trigonal-planar geometry with 120° bond angles.

AB4 Molecule

Tetrahedral geometry with 109.5° bond angles.

Octet Rule

Atoms share eight electrons for stability.

Lewis Structure

Diagram showing valence electrons in a molecule.

Trigonal-Planar Geometry

Molecule shape with three bonds at 120° angles.

Tetrahedral Geometry

Molecule shape with four bonds at 109.5° angles.

Molecular Geometry

Shape of a molecule determined by VSEPR.

Unshared Electron Pairs

Non-bonding electron pairs affecting molecular shape.

Ammonia

An AB3E molecule with a pyramidal shape.

Water

An AB2E2 molecule with bent geometry.

Bond Angles

Angles between adjacent A—B bonds in molecules.

Electron Pair Repulsion

Repulsion between electron pairs determines molecular shape.

Trigonal Planar

Shape formed by three atoms around a central atom.

Tetrahedron

Three-dimensional shape with four triangular faces.

Bonding Pairs

Electron pairs shared between atoms in a molecule.

Tetrahedral Shape

Four bonds around a central atom, 109.5° angles.

Bent Molecule

Molecule shape with two bonded atoms and lone pairs.

Ammonia

AB3E molecule with trigonal-pyramidal geometry.

Water

AB2E2 molecule with bent geometry.

Bond Angles

Angles between bonds in a molecule.

Lone Pairs

Unshared electron pairs affecting molecular shape.

Hybridization

Mixing atomic orbitals to form new orbitals.

Carbon Dioxide

AB2 molecule with linear geometry.

Chlorate Ion

AB3E molecule with trigonal-pyramidal geometry.

Lewis Structure

Diagram showing bonds and lone pairs in molecules.

Trigonal Planar

Three bonds around a central atom, 120° angles.

Trigonal Bipyramidal

Five bonds around a central atom, 90° and 120° angles.

Octahedral

Six bonds around a central atom, 90° angles.

Polyatomic Ions

Charged species with multiple atoms.

AB2E Type

Molecule with two bonds and one lone pair.

AB3E Type

Molecule with three bonds and one lone pair.

AB4 Type

Molecule with four bonds and no lone pairs.

AB2E2 Type

Molecule with two bonds and two lone pairs.

Bonding Electron Pairs

Electrons involved in covalent bonds.

Unshared Electron Pairs

Electrons not involved in bonding.

Molecular Shape

Geometric arrangement of atoms in a molecule.

VSEPR Theory

Predicts molecular geometries from electron pair repulsion.

Hybridization

Combination of atomic orbitals to form new orbitals.

sp3 Hybridization

Hybridization involving one s and three p orbitals.

Tetrahedral Geometry

Molecular shape with four bonds at 109.5° angles.

Ammonia (NH3)

Molecule with trigonal pyramidal geometry from sp3 hybridization.

Water (H2O)

Molecule with bent geometry due to lone pairs.

Carbon's Valence Electrons

Four electrons in 2s and 2p orbitals for bonding.

Hybrid Orbitals

Equal energy orbitals formed from atomic orbital combination.

Intermolecular Forces

Attractive forces between molecules, weaker than covalent bonds.

Boiling Point

Temperature where liquid particles overcome intermolecular forces.

sp Hybrid Orbitals

Formed from one s and one p orbital for linear geometry.