L3 Organics

Structural Isomer

Atoms are arranged differently with same molecular formula

Geometric Isomer

Same order of connectivity, but different arrangement

Optical Isomer

Non superimposable mirror images with a chiral carbon center

Conditions for optical isomer

• chiral carbon center

• Four different atoms/groups bonded to same carbon

Substitution for Alkene and addition Alkane (Br2 reagent)

Added to an alkane with presence of UV light and a slow substitution will occur, it slowly decolorise from orange/brown very slowly

added to an alkene, it will rapidly decolorise as an unsaturated molecule undergoing addition

Addition (Halogenation) reagent: X2/HX

Where a halogen molecule or hydrogen halide adds across a double bond

Hydrogenation ( Alkene to Alkane) Reagent: Ni at 150, or Pt

Where a hydrogen molecule adds across the double bond of an alkene to form an alkene

Hydration ( Alkene to Alcohol) Reagent: H20/H+ H2SO4- dilute

When alkene reacts with water in acidic conditions to form an alcohol

L3 Reactions

Lucas Reagent: Conc Hcl/ZnCl2

removal of an alcohol group and replace with haloalkane

Tertiary Alcohol: immediate reaction

Secondary Alcohol: slow reaction around 2 min

Primary Alcohol: very slow, no visible reaction

Alcohol Oxidation

Reagent: SOCl2,PCl3,PCl5

Primary: alcohol to aldehyde to carboxylic acid

Secondary: alcohol to ketone

Distillation (aldehyde) reagent: H+/Cr2O72-

Aldehydes have a lower boiling point than alcohol, so the reaction mixture is heated and forms evaporation and a condenser is set up to remove aldehyde

Reflux ( Carboxylic Acid) H+/MnO4- or H+/Cr207-

Reaction mixture is heated to increase the rate of reaction and a condenser is set up to condense the aldehyde back into reaction mixture increasing the yield forming a carboxylic acid

Distillation (Aldehyde) P.A.D

Purpose: to seperate substance based on different boiling point, preventing futher reactions

Advantages: can be used to purify mixtures, by separating the substance

Disadvantage: only allows separation based on boiling point

Reflux ( Carboxylic Acid) P.A.D

Purpose: allows heating of reaction mixtures to max yield and reaction rates without the loss of volatile substance

Advantage: max yield while increasing the rate of reaction

Disadvantage: superheating and risk breakage of glassware

Yield

Amount of product obtained from a chemical reaction, eg: higher yield more product

Volatile

Tendency of a substance to vaporise into a gas at a given time