Isomerism+(24.4)

Introduction to Isomers!

Isomerism can be defined as the existence of [|molecules] that have the same number of analogous [|atoms] while also differing in chemical and physical properties. These properties may include color, solubility, or rate of reaction with a certain reagent. There are two main types of isomers:

Definition --> __**Structural Isomers**__: molecules that contain different bonds. Definition --> __**Stereoisomers**__: molecules that contain the same bonds but function differently in that there are different ways that the ligands can occupy space around the metal center.

__ Structural Isomerism __ While there are many different types of structural isomerism, this particular chapter is concerned with two: __Linkage Isomerism__ and __Coordination-sphere isomers.__ __﻿____Linkage Isomerism-->__ Structural isomers of coordination compounds in which a ligand differs in its mode of attachment to a metal ion. i.e. The nitrate ion __Coordination-sphere isomers-->__ Structural isomers of coordination compounds in which the ligands within the coordination sphere differ. i.e. a violet/green colored compound in which water is either included in the sphere or displaced from the sphere to give off a different color.

__Stereoisomerism__ These isomers are composed of the same bonds as another molecule but experience a different arrangement. __Geometric Isomerism__ is a form of isomerism in which the arrangement of the constituent is different even though the exact same bonds are at hand.

__ Optical Isomerism/enantiomer __ is another type of stereoisomerism. These bonds, however, are mirror images of another molecule that cannot be superimposed.

i.e. Think of the resemblance between your left and right hand when you look at one in a mirror! It resembles the other! -the isomer that remembles a “right handed” plane of polarization (rotates right) is considered __dextrorotatory.__ The isomer that resembles a “left handed” plane of polarization (rotates left) is considered __levorotatory.__ This rotation of polarized light creates an optically active solution, meaning that the plane of light can then be rotated relative to the point of view of the observer.

﻿*please enjoy the following flow chart as it depicts a visual understanding of classifying isomers*
 * ||  || Isomers (same formula,different properties) ||   ||   ||
 * || Structural Isomers (different bonds) ||  || Stereoisomers (same bonds, different arrangement) ||   ||
 * Coordination-sphere Isomers || Linkage Isomers ||  || Geometric Isomers || Optical Isomers ||

"Isomerism (chemistry) -- Britannica Online Encyclopedia." //Encyclopedia - Britannica Online Encyclopedia//. Web. 24 Mar. 2011. . Brown, Theodore L., and H. Eugene Lemay, Jr. "24.4/Isomerism." //Chemistry: The Central Science 11E//. Upper Saddle River: Pearson Education, 2009. 1026-031. Print.