Flashcards in Properties and uses of Crude Oil Deck (19):
Crude oil is mostly [ ]
What are alkanes made up of
Chains of carbon atoms surrounded by hydrogen atoms
What are the first 4 alkanes?
What is the formula and structure of methane?
H -- C -- H
What is the formula and structure of ethane?
C₂H₆ H H
H -- C -- C -- H
What is the formula and structure of propane?
C₃H₈ H H H
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H -- C -- C -- C -- H
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H H H
What is the formula and structure of butane?
C₄H₁₀ H H H H
| | | |
H -- C -- C -- C -- C -- H
| | | |
H H H H
What does each straight line on a diagram of an alkane represent?
A covalent bond
What does the term saturated mean?
The atoms have formed bonds with as many other atoms as they can - carbon atoms form 4 bonds and hydrogen atoms form 1 bond
What is the general formula for an alkane?
The [ ] the molecules, the more runny the hydrocarbon - the less [ ] (gloopy) it is
What does 'more volatile' mean?
The molecules turn into a gas at a lower temperature
The shorter the molecules, the [ ] volatile they are therefore, the lower the temperature at which the [ ] vaporises or [ ] and the lower its [ ] point.
The shorter the molecule the more [ ] the hydrocarbon is
What is refinery gas used for? Why?
Used for bottled gas. The refinery gas fraction has the shortest molecules therefore it has the lowest boiling point - its gas at room temp
What is petrol used for? Why?
Petrol is a liquid which is ideal for storing in the fuel tank of a car. It can flow to the engine where its easily vaporised to mix with the air before it's ignited - it has longer molecules so it has a higher boiling point
What 2 things helps to decide the use of different fractions?
The volatility and the viscosity
What are really viscous hydrocarbons used for?
Lubricating engine parts and for covering roads