BenzeneBenzene

Barbora BakajováBarbora Bakajová

Tereza ŠimšováTereza Šimšová

What is benzene?What is benzene?

BenzeneBenzene

an organic chemical compoundan organic chemical compound a colorless and flammable liquid with a a colorless and flammable liquid with a

pleasant, sweet smell pleasant, sweet smell a known carcinogena known carcinogen a component of gasoline a component of gasoline production of drugsproduction of drugs ,plastics, synthetic rubber, ,plastics, synthetic rubber,

and dyesand dyes flammable - hořlavýflammable - hořlavý

HistoryHistory

was discovered in 1825 by the English was discovered in 1825 by the English scientistscientist Michael FaradayMichael Faraday

he isolated it from oil gas and gave it the name he isolated it from oil gas and gave it the name bicarburet of hydrogenbicarburet of hydrogen. .

In1833, the German chemist Eilhard In1833, the German chemist Eilhard Mitscherlich produced it by the distillation of Mitscherlich produced it by the distillation of benzoic acid and lime. benzoic acid and lime.

SymbolsSymbols

Two version:Two version:

1) the delocalised electrons are represented by 1) the delocalised electrons are represented by a circle within the hexagon a circle within the hexagon

2) the Kekulé form where alternate single and 2) the Kekulé form where alternate single and double bonds are shown. double bonds are shown.

StructureStructure

structure is called a structure is called a resonance hybridresonance hybrid. .

mesomeric structuremesomeric structure

This delocalisation of electrons is known as This delocalisation of electrons is known as aromaticity, and gives benzene great stabilityaromaticity, and gives benzene great stability

PropertiesProperties

molar mass:78,11 g/molmolar mass:78,11 g/mol density:0,8786 g/cmdensity:0,8786 g/cm33

pphase:hase: liquidliquid melting point:5,5 °C (278.6 K)melting point:5,5 °C (278.6 K) boiling point:80.1 °C (353.2 K)boiling point:80.1 °C (353.2 K) viscosity:0.652 cP at 20°Cviscosity:0.652 cP at 20°C molecular shapemolecular shape :planar:planar

UsesUses

an industrial solvent and degreasing metalan industrial solvent and degreasing metal increases the octane ratingincreases the octane rating derivatives of benzene :derivatives of benzene :

- styrene- styrene :polymers and plastics :polymers and plastics

- phenol- phenol :resins and adhesives :resins and adhesives

- cyclohexane- cyclohexane :nylon manufacture :nylon manufacture degreasing-odmašťovánídegreasing-odmašťování

resins-pryskyřiceresins-pryskyřice

Reactions of benzeneReactions of benzene

1)S1)SRR halogenations of alkylhalogenations of alkyl bebennzene side-chainzene side-chain 2)A2)AE E addition on C=C of alkyl benzenesaddition on C=C of alkyl benzenes 3)A3)AR R reduction of aromatic hydrocarbonsreduction of aromatic hydrocarbons 4)S4)SEEArAr Friedel Crafts alkylation Friedel Crafts alkylation ,acylation,acylation 5)Oxidation of alkyl benzene side-chain5)Oxidation of alkyl benzene side-chain

Reaction of benzene Reaction of benzene

Friedel-Crafts alkylationFriedel-Crafts alkylation SSEEArAr

the Friedel-Crafts alkylation involves the the Friedel-Crafts alkylation involves the alkylation of an aromatic ring (such as alkylation of an aromatic ring (such as benzene) and an alkyl halide using a strong benzene) and an alkyl halide using a strong Lewis acid catalyst. Lewis acid catalyst.

Health effectsHealth effects

bbreathingreathing :very high levels :very high levels →death→death,,also headache, also headache, tremors, confusion,….tremors, confusion,….

eating or drinking foods containing high levelseating or drinking foods containing high levels::

irritation of the stomach, convulsions, rapid heart irritation of the stomach, convulsions, rapid heart rate, and death convulsionsrate, and death convulsions

chronic effectchronic effect :damages bone marrows:damages bone marrows ,leads to ,leads to anemanemmmiaia

tremor-třestremor-třes convulsion-křečconvulsion-křeč bone marrow-kostní dřeňbone marrow-kostní dřeň

SourcesSources

wikipedia.org/wiki/Benzene wikipedia.org/wiki/Benzene Organic chemistry-lectures(VUT)Organic chemistry-lectures(VUT)

Thank you for your attentionThank you for your attention