Definitions in Optical Isomerism

Define specific rotation

The rotation in degrees caused by a solution containing 1g/mL of a substance in a polarimeter tube of 1 dm length, when D-line light of sodium is used.

Define Optical activity

Property of a substance to rotate the plane of the plane-polarized light through a definite angle.

Define assymetric/chiral carbon

A carbon atom linked to 4 different atoms or groups

Define chiral centre

A carbon atom linked to 4 different atoms or groups

What are the conditions for geometrical isomerism?

the molecule must have a double bond. there must be two different atoms or groups attached to each carbon atom of the double bond.

What are the conditions for optical activity?

assymetric carbon. the molecule should have non-superimposable mirror image. the molecule should not have plane of symmetry.

Do meso compounds have a plane of symmetry?

yes

Does a meso compound contain chiral atoms?

yes

Racemic mixture is optically inactive due to ____

external compensation

Meso compounds are inactive due to ____

internal compensation

Define resolution

Separation of a racemic mixture into its constituents d and l compounds.

Define Assymetric Synthesis.

Preparing either a d-compound or an l-compound

Define racemic mixture

mixture of d and l in equal amounts.

Difference b/w racemic mixture and meso compound

i) contains two kinds of optically active molecule vs contains same kind of optically inactive molecule
ii) can be resolved into active components vs cannot be resolved
iii) optically inactive due to external compensation vs optically inactive due to internal compensation

Define enantiomers

Pair of optical isomers which are non-superimposable miror images of each other

Define diastereomers

Stereoisomerrs of same compound other than enantiomers.

Acidic nature of oxyacids and oxides along period and down the group?

increases. decreases.

Difference b/w diastereomers and enantiomers

i) stereoisomers with no mirror image relation vs have a mirror image relation
ii) different physical properties vs similar physical properties
iii) can be separated by physical methods vs cannot be separated by physical methods
iv)have rotation in same direction but to different extent vs have rotation in opposite direction but to same extent

Difference b/w chiral compound and racemic mixture

i) single compound vs pair of chirals
ii) always optically active vs optically inactive due to external compensation

What is the law of definite proportions?

It states that the same compound is always composed of the same elements combined together in the same or fixed proportions by weight.

What is the law of multiple proportions?

It states that if two elements combine together to form several compounds, then the weight of one of these elements, which combines with a fixed weight of the other, are in ratio of simple whole numbers.

What is the law of reciprocal/equivalent proportions?

It states that if two elements A and B combine with a fixed mass of element C to form two compounds, then the ratio of A and B in these compounds is same or simple multiple of the ratio when they combine with each other.

Citric acid

2-hydroxy propane-1,2,3-tricarboxylic acid

Maleic acid

Z-ethene-1,2-dicarboxylic acid

Fumaric acid

E-ethene-1,2-dicarboxylic acid

Malic acid

2-hydroxyethane-1,2-dicarboxylic acid

Mandelic acid

2-hydroxy 2-phenyl ethanoic acid

Lactic acid

2-hydroxy propanoic acid

Tartaric acid

2,3-dihydroxy butane-1,4-dioic acid

Propylene glycol

propane-1,2-diol