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Fuels From Crude Oil
This set contains information about fuels. For more information go to polymers and plant oils
31
Chemistry
9th Grade
12/15/2012

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Cards

Term
Define: Combustion
Definition
A substance which burns in oxygen to produce heat energy
Term
When Carbon is heated srongly in oxygen a gas is formed. What is the name and formula of the gas?
Definition

Carbon Dioxide

CO2

Term
Which test identifies Carbon Dioxide? What would you see if this gas was present?
Definition
You would put it in limewater. The limewater will turn cloudy if COis present.
Term
What is the name given to the type of reaction in which substances combine with oxygen?
Definition
Oxidation
Term
What do we call reactions which give out heat energy?
Definition
Exothermic
Term
What is the general formula for alkanes?
Definition
CnH2n+2
Term
What is a hydocarbon?
Definition
A molecule which only contains hydrogen and carbon
Term
What does Saturated mean?
Definition
There are no double bonds (only single bonds)
Term
What is distillation?
Definition

This is when a substance is boiled so it evaportaes, it then is cooled whien it hits a cold surface and finally turned back into a liquid

(heat, evaporate, condense)

Term
Which fractions in oil evaporate first?
Why?
Where are they collected in a fractioning column?
Definition
The ones with the least amount of hydrocarbons as there boiling point is lower.
They are collected at the top as they have a lower boiling point.
Term
What does a catalyst do?
Definition
It speeds up reactions
Term
What does an oil refinery do with less valuable fraction?
Definition
They convert it into a useful fraction.
Term
What is the main impurity in crude oil?
Definition
Sulphur
Term
Which part of the fractioning column is hot and which is cold?
Definition
The bottom is hot the top is cool.
Term
What is fractional distillation?
Definition
A separation process that uses the differences in boiling points to separate the hydrocarbon into fractions.
Term
How does a fractioning column work?
Definition
The crude oil is heated until it vaporises and the hot vapour is fed in near the bottom of the fractioning column.
The vapours rise up the fractioning column, cooling as they rise and condensing at different temperatures.
Vapours condense onto a tray when they reach the part of the column which is just cooler than their boiling point so they are collected in their fractions as different levels. Hydrocarbons with the smallest molecules are collected ar the top of the tower as they have the lower boiling points.
The bottom of the tower has fractions which have high boiling points. These cool to form very thick liquids or solids at room temperature.
Term
What happens to the boiling point as hydrocarbon size increases?
Definition
It increases
Term
What happens to the viscosity as hydrocarbon size increases?
Definition
It increases
Term
What happens to flammability as hydrocarbon size increases?
Definition
It decreases.
Term
Why do alkanes get thicker and less runny as the length of the carbon chain increases?
Definition
Theere are more forces of attraction when the number of hydrocarbons is small so as hydrocarbon size increases forces of attraction decrease as there is a higher surface area.
Term
What are the products of complete combustion?
Definition
Carbon dioxide and water vapour
Term
What the the products of incomplete combustion?
Definition
Carbon Monoxide
Term
How is acid rain formed?
Definition
Sulphur reacts with the oxygen to create sulphur dioxide. The carbon dioxide dissolves into water and produces acid rain when combined with sulphur
Term
What does a Catalytic converter work?
Definition
It converts nitrogen oxides and carbon monoxide into nitrogen and carbon dioxide.
Term
Name an alternative fuel?
Definition
Biodiesel
Ethanol
Hydrogen
Term
Define: Viscosity
Definition
How easily something flows
Term
What is the smallest alkane molecule?
Definition
Methane
Term
Define: Flammability
Definition
How easily something burns.
Term
Which effect is produced by greenhouse gases?
Definition
Global Warming
Term
What are some problems with using hydrogen as an alternative fuel?
Definition
Hydrogen is explosive
It is expensive to extract as it require electrolysis
Special engines are needed to use hydrogen in cars
Term
Out of Hydrogen,ethanol and biodiesel which is the most efficient?
Definition
Hydrogen
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