Exp-12-HYDROCARBONS

Hydrocarbons

Main classes of hydrocarbons based on structure

Open-chain and Closed-chain

Distinguishing feature of unsaturated hydrocarbons

Presence of double or triple bonds

Saturated hydrocarbons

Alkanes

Bonds characteristic of unsaturated hydrocarbons

Pi bonds

Hydrocarbons inert towards HCl and H2SO4 at room temp.

Saturated hydrocarbons

Purpose of Baeyer's test

Detecting the presence of unsaturated hydrocarbons

Change in color of permanganate solution with unsaturated hydrocarbons

Decolorizes

Type of hydrocarbon that reacts by substitution under rigorous conditions

alkanes

Characteristic reactions of unsaturated hydrocarbons

Addition reactions

Bonds found in saturated hydrocarbons

Sigma bonds

Not a characteristic reaction of unsaturated hydrocarbons

Substitution

Hydrocarbon class with benzene rings

Aromatics

Product of Baeyer's test when unsaturated hydrocarbons react with permanganate

MnO2

Alkenes and alkynes

Unsaturated hydrocarbons

The reaction type involved in the breaking of pi bond in unsaturated hydrocarbons

Addition

Bonds contributing to conjugative stability in aromatic compounds

Pi bonds

Reaction that aromatic compounds primarily undergo

Electrophilic aromatic substitution

Property of the ring system preserved in aromatic substitution reactions

Resonance

Mechanism in aromatic substitution of an electrophile

Two steps

Reactions aromatic compounds resist due to the risk of destroying the ring system

Electrophilic addition

Position of substitution in bromination of acetanilide due to steric inhibition

Para

What type of director is the Amide group in benzene ring of acetanilide during bromination

Activating, ortho-para director

Substitution illustrated in bromination of acetanilide

Electrophilic substitution

Purpose of the ignition test

To identify the flammability of hydrocarbons

Luminous flame in the ignition test indicates

Presence of impurities in the hydrocarbon

Placing a dry evaporating dish over the flame during the ignition test

To collect soot formed during combustion

Hydrocarbon used in place of benzene during the ignition test

n-Hexane

Repeating the ignition test with different hydrocarbons

To compare the flammability of different hydrocarbons

Purpose of adding NaOH to KMnO4 solution in Baeyer's Test

To make the solution alkaline

Purpose of setting aside 1 mL of the prepared KMnO4 solution as standard in Baeyer's Test

To serve as a control sample

Color indicating a positive result for unsaturation in Baeyer's Test

Brown

Precaution advised while performing Baeyer's Test

Perform the test in a hood

Role of glacial acetic acid in Electrophilic Aromatic Substitution

Solvent

Amount of bromine in acetic acid solution added in Electrophilic Aromatic Substitution

0.76 mL

Purpose of stirring the solution for 3 minutes more in Electrophilic Aromatic Substitution

To accelerate the reaction

Positive result in Electrophilic Aromatic Substitution using acetanilide

Solution turning cloudy

Compound used instead of acetanilide in repeated steps a-c of Electrophilic Aromatic Substitution

Naphthalene

Step in Electrophilic Aromatic Substitution performed using the hood

Adding bromine in acetic acid solution