SC8 Flashcards
what is crude oil separated into?
Different hydrocarbon fractions
How is crude oil formed?
Over millions of years and high temperatures and pressures from the battery, domains of plants and animals
What is crude oil?
A complex mixture of lots of different hydrocarbon compounds, which contain just hydrogen and carbon hydrogen and carbon found in the crude oil have their carbon atoms arranged in either chains or rings and I’m mostly alkanes
what is the highest fraction that crude oil separated into?
gasses (3 carbons)
What is the bottom fraction that crude oil separated into?
bitumen- used to surface roads and roofs with 70+ carbons
what is the fraction with eight carbons?
Petrol-used to fuel cars
what is the fraction with 15 carbons?
Kerosene(paraffin)- used as a fuel in aircraft
What is the fraction with 20 carbons?
Diesel oil-diesel oil is used as a fuel in some cars and larger vehicles. E.g. trains
what is the fraction with 40 carbons?
Fuel oil-fuel oil is used as a fuel for larger ships and also in some power stations
what is a homologous series?
A family of molecules, which have the same general formula and share similar chemical properties
What are two different homologous series is of hydrocarbons
alkenes and alkanes
What are physical properties of hydrocarbons determined by?
The intermolecular forces that hold the chains together
What are some physical properties of short hydrocarbons
-shorter hydrocarbons are easy to ignites because they have a low boiling points. I tend to be gases at room temperature.
-This gas molecules mix with oxygen in the air so produce a gas mixture which burst into flames if it comes into contact with a spark
what are some physical properties of longer hydrocarbons?
Longer hydrocarbons are usually liquids at room temperature, and have a higher boiling point of a much harder to ignite
what does viscosity mean?
-Viscosity, measured how easily a substance flows
-The stronger the force between hydrocarbons molecules, the harder it is for the liquid flow
-Fractions containing longer hydrocarbons have a higher viscosity they are thick like treacle
-Fractions made up of shorter hydrocarbons, have a low viscosity and a much Runnier
What is the characteristics of the intermolecular forces between small molecules?
The intermolecular forces of attraction break a lot more easily in small molecules and they doing bigger molecules. That’s because the forces are much stronger between big molecules than they are between small molecules.
How do you fuels release energy?
Combustion reactions
What does incomplete combustion produce?
Toxic carbon monoxide and soot
Why is carbon monoxide poisonous?
-carbon monoxide can combine with red blood cells and stop your blood from doing. It’s proper job of carrying oxygen around the body.
-A lack of oxygen in the blood supply to the brain can lead to fainting or a coma or even death
why is Kevin being produced negative in incomplete combustion
-During the incomplete, combustion, tiny particles of carbon can be released into the atmosphere when they fall back to the ground, a deposit themselves as a hard black dust, we call soot
-search makes buildings look dirty, reduces the air quality and can cause or worsen respiratory system problems
what does sulphur dioxide cause?
Acid rain
How does sulphur dioxide cause acid rain?
When fossil fuels are burned their release, mostly CO2, but they also release of a harmful gases, especially sulphur dioxide and sulphur dioxide comes from sulphur impurities in the fossil fuels, and when it’s mixes with close it from statutes of uric acid and forth as acid rain
What are some negatives of acid rain?
-acid, rain closest lakes to become acidic and many plants and animals to die as a result
-Acid rain kills trees. Storage is limestone, buildings, and stone statues and can also make metal corrode.
what are some pros of hydrogen gas as a fuel
Hydrogen is very clean fuel in a hydrogen fuel cell. How do you do in combines with oxygen to produce energy and the only waste product is water no nasty pollutants like carbon dioxide toxic carbon monoxide. Orsett hydrogens obtained from water which is a renewable resource so it’s not going to run out how you doing can even be obtained from water produced by the south when is used in fuel cells