Molecular Geometry, Chemical Bonding, and Intermolecular Forces

Vocabulary flashcards covering molecular geometries, Lewis structures, bond angles, electronegativity, bond polarity ranges, intramolecular forces, and intermolecular forces with their effects on physical properties.

Bonding Site

Any single bond, double bond, or triple bond on a central atom, each counting as exactly one site when determining molecular geometry.

H bonds only occur if

H is boned to to a O, N, or F

Like dissolved like

Same bond toes dissolve the same bond types

Polar molecules dissolve

Polar molécules and ionic compounds

Non polar bonds dissolve

Nonpolar bonds

Linear shape

A molecular shape with $2$ bonding sites and $0$ lone pairs of electrons (LPE) on the central atom ex: CO2

Trigonal Planar

A molecular shape with $3$ bonding sites and $0$ lone pairs of electrons (LPE) on the central atom,

Tetrahedral

A molecular shape with $4$ bonding sites and $0$ lone pairs of electrons (LPE) on the central atom

Trigonal Pyramidal

A molecular shape with $3$ bonding sites and $1$ lone pair of electrons (LPE) on the central atom

Bent Geometry

A molecular shape with $2$ bonding sites with either $1$ or $2$ lone pairs of electrons (LPE) on the central atom

Bond Polarity

The classification of a bond based on the electronegativity difference between two bonded atoms. ex: nonpolar covalent

Electronegativity

A measure of how likely an atom is to attract a bonding pair of electrons toward itself in a chemical bond.

Nonpolar Covalent Bond

A bond where electrons are shared equally, resulting in no charge separation and an electronegativity difference of $0 - 0.4$.

Polar Covalent Bond

A bond where electrons are shared unequally, producing partial charges and having an electronegativity difference ranging from $0.41 - 2.0$.

Ionic Bond

A chemical bond where electrons are not shared but transferred, resulting in full charges and an electronegativity difference of $2.1\text{ and up}$.

Intramolecular Forces

Forces within a molecule that hold atoms together (chemical bonds), responsible for macroscopic properties like electrical conductivity, hardness, and luster.

Intermolecular Forces (IMFs)

Attractions between separate particles or neighboring compounds that hold molecules together in liquids and solids.

London Dispersion Forces

The weakest category of intermolecular forces, occurring between nonpolar molecules (such as in $CCl_4$ or $Br_2$).

Dipole-Dipole Forces

Intermolecular forces of moderate strength occurring between polar molecules (such as in $HCl$).

Hydrogen Bonding

A strong intermolecular attraction that occurs only when hydrogen is covalently bonded to a highly electronegative atom: $F$, $O$, or $N$.( polar)

Ion-Dipole Forces

The strongest category of intermolecular forces, occurring between an ion and a polar molecule (such as $NaCl$ or $KCl$ dissolved in water).( polar)

Surface Tension

An inward force and attraction of particles in a liquid's surface layer that tends to minimize surface area. More surface tension- stronger IMF

Evaporation in relation to IMF

Quicker evaporation rate = lower IMF( vice - versea)

Boiling Point Relationship to IMFs

The principle that stronger intermolecular forces require more kinetic energy and higher temperatures to separate particles, resulting in higher boiling and melting points.

Evaporation Rate Relationship to IMFs

The principle that as the strength of intermolecular forces increases, molecules escape less readily into the gas phase, leading to a slower rate of evaporation.