Electronegativity and Molecular Polarity

This set of flashcards covers important vocabulary and concepts related to electronegativity, bond polarity, and molecular polarity.

Electronegativity

The ability of atoms in a molecule to attract electrons to themselves.

Trends in Electronegativity

Electronegativity increases from left to right across a row and from the bottom to the top of a column on the periodic table.

Polar Covalent Bonds

Bonds where the difference in electronegativity between bonded atoms leads to unequal sharing of electrons.

Bond Polarity Scale

The classification of bond polarity based on electronegativity difference: >2.0 ionic, 0.5 – 2.0 polar covalent, <0.5 non-polar.

Ionic Bond

A bond typically formed between a metal and a non-metal, where the electrons are transferred and not shared.

Polar Covalent Bond

A bond formed between two different non-metals where electrons are shared unequally.

Non-Polar Covalent Bond

A bond where electrons are shared equally, usually between identical atoms.

C-H Bond in Organic Chemistry

Considered to exhibit equal sharing in organic chemistry.

Molecular Polarity

Determined by the symmetry of the molecule; asymmetric molecules are polar, symmetric ones are non-polar.

Factors Influencing Polarity

The distribution of charge within a molecule affects physical properties like boiling points and solubility.

Asymmetric Molecules

Molecules that have an uneven distribution of charge and are considered polar.

Symmetric Molecules

Molecules that have an even distribution of charge and are considered non-polar.

Molecular Geometry Types

Includes fully symmetric structures (linear, trigonal planar, tetrahedral) and asymmetric structures (bent, trigonal pyramidal).

Procedure to Determine Polarity

1. Draw the Lewis structure. 2. Determine the molecular geometry. 3. Identify if bent or trigonal pyramidal (polar) or if surrounding atoms are identical/asymmetric.