Science- Chemistry 1b

Cracking- turning long chained molecules into shorter one's- makes Alkanes and Alkenes.

Smaller molecules more useful, e.g. Petrol.

To do this you must vapourise it and pass it over a catalyst.

Crude oil is separated by Fractional distillation, in a column. 

Bottom of column is hottest and thickest- longer molecules.

Top of column is gases.

Alkane molecules have a single bond- saturated. Formular- Cn2n+2

Alkene molecules have a double bond- unsaturated because they can make more links. formular- CnC2n  Double the amount of hydrogen molecules.

Plant oils are extracted form food by squeezing and crushing them, they contain essential fatty acids.

Oils dont dissolve in water, mixing oil and water makes a emulsion- this is when droplets of one liquid are suspended in another liquid. e.g. mayonnaise is an emulsion of olive oil and vinegar.  

Vegetable oils can be turned into fuels.

Biodiesel is made form begetable oils and is a renewable source- good for the environment.

vegetable oils are unsaturated (good) and animal fats are saturated (bad)- saturated increase the cholesterol on the blood.