Key Concepts in Chemical Bonding and Molecular Structure

Valence Electrons

Electrons in the outermost shell of an atom.

Lewis Structure

Diagram showing bonds and lone pairs in molecules.

Structural Formula

Representation of molecule showing arrangement of atoms.

Lone Pair of Electrons

Two electrons not involved in bonding.

Covalent Bond

Bond formed by sharing electron pairs.

Electronegativity

Tendency of an atom to attract electrons.

Polar Molecule

charge distribution is also asymmetric so there are partial charges on the molecule

Polar bond

Uneven distribution of electrons, one side of the molecule being positive will other is negetive - asymetrical

Non-Polar Bond

molecule that has no electrial charge of partical charge - symmetrical

Molecular Symmetry

parts can be interchanged without changing the overall structure or orientation of the molecule

Structural Isomers

Compounds with the same formula but different structures.

Ionic Bond

Bond formed by the transfer of electrons.

Metallic Bond

Bond formed by delocalized electrons in metals.

Delocalized Electrons

Electrons that are spread over multiple atoms.

Alloy

Mixture of two or more metals.

Interstitial Alloy

Alloy with smaller atoms fitting between larger ones.

Substitutional Alloy

Alloy where some metal atoms are replaced.

Molecular Dipole

Separation of charge within a molecule.

Column 1 2 7

linear •-• •-•-•

Column 3

triangular planer

Column 4

Terahedral

Column 5

Peramiddle

Column 6

bent

groups 2 3 4

symetrical - if surroundings are the same

groups 5 6

- asymetrical

meth-

1 carbon

eth-

2 carbons

prop-

3 carbons

but-

4 carbons

pent-

5 carbons

hex-

6 carbons

hept-

7 carbons

oct-

8 carbons

non-

9 carbon

dec-

10 carbons

-ane

single bond

-ene

double bond

-yne

triple bond

Oxygen (O2)

nonpolar

Nitrogen (N2)

nonpolar

Carbon Diozide (CO2)

nonpolar

most hydrocarbons like oil and gasoline are

nonpolar

water (H2O)

polar

Ammonia (NH3)

polar

Sulfer Dioxide (SO2)

polar

noble gases like helium neon and argon are

nonpolar