Polarity of Molecules

Vocabulary flashcards on molecular polarity.

Polar Molecule

A molecule with an uneven distribution of charge, resulting in a positive and negative end.

Non-polar Molecule

A molecule with an even distribution of charge, resulting in no overall dipole.

Electronegativity

A measure of the ability of an atom in a chemical compound to attract electrons.

Dipole Moment

A measure of the polarity of a chemical bond within a molecule.

Symmetrical Molecule

A molecule where the shape and distribution of charge are uniform.

Asymmetrical Molecule

A molecule where the shape and distribution of charge are non-uniform.

Tetrahedral Shape

Molecular geometry with a central atom bonded to four atoms at the corners of a tetrahedron.

Trigonal Planar Shape

Molecular geometry with a central atom bonded to three atoms in a plane.

Bent Shape

Molecular geometry where three atoms are bonded in a non-linear arrangement.

Polar Bond

A covalent bond in which electrons are shared unequally.

Charge Distribution

The way electric charge is spread out in a molecule or system.

Molecular Shape

The three-dimensional arrangement of atoms that constitute a molecule.

Regions of Negative Charge

Areas around an atom where valence electrons are concentrated.

Minimize Repulsion

Arranging atoms to reduce electron cloud interaction, influencing molecular shape.

Central Atom

The atom in a molecule to which all other atoms are bonded.

Bonded Atoms

Atoms that are chemically linked together by covalent or ionic bonds.

Lone Pair

A pair of valence electrons that are not shared with another atom in a covalent bond.

Overall Dipole

Net dipole moment resulting from the sum of all individual bond dipoles in a molecule.

Slightly Positive End

The end of a polar molecule with a partial positive charge.

Slightly Negative End

The end of a polar molecule with a partial negative charge.

Intermolecular Forces

Attractive or repulsive forces between molecules.

Valence Electrons

The electrons in the outermost shell of an atom that participate in chemical bonding.

Charge Separation

Unequal distribution of electron density leading to partial charges.

Molecular Geometry

The three-dimensional arrangement of atoms in a molecule.

Lewis Structure

Diagram representing the valence electrons of atoms within a molecule.

Electron Density

Measure of the probability of finding an electron at a specific location.

CCl4

Carbon Tetrachloride, an example of a non-polar molecule with tetrahedral geometry.

SO2

Sulfur Dioxide, an example of a polar molecule with bent geometry.

Repulsion

The force that causes atoms to move away from each other.

Bond Angle

The angle between two adjacent bonds at the central atom.

VSEPR Theory

Valence Shell Electron Pair Repulsion theory predicts the geometry of molecules from the number of electron pairs surrounding their central atoms.

Lone Pair Repulsion

The repulsive force between lone pairs of electrons which affects molecular geometry.

Bond Pair

A pair of electrons shared between two atoms in a covalent bond.

Bond Length

The distance between the nuclei of two bonded atoms.

Resonance Structure

One of two or more Lewis structures that can be drawn for a molecule.

Formal Charge

The charge an atom would have if all bonding electrons were shared equally.

Oxidation State

A measure of the degree of oxidation of an atom in a chemical compound.

Dipole Additions

When polar bonds combine to create an overall dipole moment.

Dipole Cancellation

When the effects of polar bonds neutralize, and there is no overall dipole moment.

Bond Moment

The dipole moment of a single bond in a molecule.

Non-bonding Region

Region with a lone pair of electrons and is not involved in a covalent bond.

Bonding Region

Region where electrons are shared between atoms.

Hybridization

The concept of mixing atomic orbitals into new hybrid orbitals.

sp3 Hybridization

Hybridization involving one s and three p orbitals, seen in tetrahedral geometries.

sp2 Hybridization

Hybridization involving one s and two p orbitals, seen in trigonal planar geometries.

sp Hybridization

Hybridization involving one s and one p orbital, seen in linear geometries.

Vector Sum

The resultant dipole moment, calculated by adding the bond moments as vectors.

Molecular Polarity

The overall polarity of a molecule, determined by the vector sum of bond polarities and lone pairs.

Linear Shape

Molecular geometry where atoms are arranged in a straight line.

Regions of Electron Density

Areas around a central atom that contain bonding pairs or lone pairs of electrons.