Alkanes are hydrocarbons, this means they only contain hydrogen and carbon

They are the simplest type of hydrocarbon and consist only of single bonds


Notice how carbon has four arms, this is because it wants to bond with four other atoms
Notice how carbon has four arms, this is because it wants to bond with four other atoms

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The alkanes you need to know are the first 8, from methane to octane
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PROPERTIES OF ALKANES


1) SOLUBILITY

They are insoluble in water and form layers; alkanes are said to be immisicible (they don't mix)


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This is why disasters like the Rena Oil Spill and the Gulf of Mexico are so hazardous for the environment

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2) STATE

The first 4 alkanes are gas at room temperature
Pentane (5 carbons) to octadecane (18 carbons) are liquid
Nonadecane (19 carbons) and above are solid

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Candles are made of solid alkanes
Candles are made of solid alkanes
Petrol contains about 90% octane, a liquid alkane
Petrol contains about 90% octane, a liquid alkane












3) TRENDS IN MELTING AND BOILING POINTS

The melting and boiling points increase as the alkane carbon chain gets longer



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4) USED AS FUELS

They are highly flammable and the main use of alkanes is as fuels (see combustion)


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