Crude Oils And Fuels Flashcards
(27 cards)
What is crude oil made up of?
It is a mixture of a very large number of compounds
How are things separated by fractional distillation?
Each compound in the crude oil vaporises and condenses at different temperatures, so they are separated.
What compounds are in crude oil?
Mostly saturated hydrocarbons called alkanes
What is crude oil used for?
To produce fuels and chemicals and it has a limited resource
What gases are released when fuels are burnt?
Carbon dioxide, water vapour, carbon monoxide, sulfer dioxide and oxides of nitrogen into the atmosphere.
What happens in the combustion of hydrocarbon fuels?
They release energy and during the combustion the carbon and hydrogen fuels are oxidised
What are some bad things that gases cause?
Suffer dioxide causes acid rain
Carbon dioxide causes global warming
Solid particles cause global dimming
How are biofuels produced?
From plant material
Advantages of biofuels
Produce less greenhouse gases than fossil fuels when burnt
Are alternative sources to fossil fuels
May not produce any particulates like soot
Disadvantages of biofuels
High cost of production
Shortage of food
Industrial pollution- dust and noise pollution
What is cracking?
When hydrocarbons are broken down smaller more useful molecules. This involves heating large alkanes with a catalyst or steam and hot temperature decomposes to make the hydrocarbon smaller molecules, alkenes.
Examples of alkanes:
Methane
Ethane
Propane
Butane
Examples of alkenes:
Ethene
Propene
How do you express a double bond?
=
What is the test the presence of double bonds?
Bromine water turning from orange to colourless
How do you make polymers?
Many small molecules join together to form very large molecules
How is ethanol produced?
By fermentation with yeast, using renewable sources
Sugar=carbon dioxide + ethanol
How do you extract vegetable oil?
The plant material is crushed and the oil is removed by pressing or distillation. Water and other impurities are removed
Why is vegetable oil better to cook with than water?
Because it has a higher boiling point so it can cook food at higher temperatures
What is an emulsion?
They are thicker than oil or water hand have many uses that depend of their special properties.
What are emulsifiers?
They have a hydrophilic head and a hydrophobic tail. This causes them to join oils and water together.
How is unsaturated vegetable oil hardened to make margarine?
By reacting them with hydrogen in the presence of a nickel catalyst at about 60 degrees C.
What are the layers of the earth?
Core
Mantle
Crust
What is Wegener’s theory?
Continental drift
Evidence- same species in different continents
No believed because- no evidence and people believed the creation theory
