Organic Chemsitry Part 1 Flashcards
What is a hydrocarbon?
A hydrocarbon is compound of hydrogen and carbon ONLY.
What are the characteristics of compounds in a homologous series?
In a homologous series, compounds:
1. Have the same general formula
2. Contain the same functional group
3. Share similar chemical properties
4. Follow a trend in physical properties.
True of false: Alkanes are a an example of a homologous series.
True
What is the general formula for alkanes?
CnH2n+2
What is an isomer?
Isomers are compounds that have the same molecular formula but a different displayed formula.
What is the difference between a molecular formula and a displayed formula?
Molecular = shows how many atoms there are in a molecule of an element.
Displayed = shows all the bonds between all of the atoms in a molecule.
True or false: isomers can have different properties.
True
Go on chat GPT and do some practise of drawing isomers.
Check them. If done badly, say you don’t understand card.
What are the first 6 members of the alkane homologous series, and their formula?
Methane = CH4
Ethane = C2H6
Propane = C3H8
Butane = C4H10
Pentane = C5H12
Hexane = C6H14
What is an alkane?
Alkanes are saturated hydrocarbons. This means they only have single bonds.
What is crude oil?
Crude oil is a mixture of hydrocarbons?
Why is crude oil not useful?
It is not useful as a mixture because there are too many substances within it with different boiling points.
But it can be separated into 6 smaller mixtures of hydrocarbons called, fractions.
What properties do hydrocarbons within a fraction share?
- similar sized hydrocarbons
- similar boiling points
This is because a larger hydrocarbon has stronger intermolecular forces, and to overcome them, they need more heat, leading to a higher boiling point.
Why do hydrocarbons become more viscose as the length of their carbon chain increases?
More carbons in the same area, causing it to be more tightly packed, making the carbon chain to become tangled.
What happens to the viscosity,flammability, and boiling points of hydrocarbons as they become larger?
- the boiling point will increase
- the viscosity will increase
- the become less flammable
True or false: boiling point = condensation point
True
How would one carry out industrial fractional distillation?
- The crude oil is heated and vaporised. It is then passed into the bottom of a fractionating column and the gas will rise.
- The temperature of the fractionating column is controlled for it to be cooler at the top, and hotter at the bottom.
- The hydrocarbons will rise and begin to cool down and condense back to a liquid at its boiling point.
- Each liquid fraction is then piped off, while the gases with lower boiling points continue to rise.
- The fractions are separated with the higher boiling points collected near the bottoms and the smaller fractions with lower boiling points are collected nearer the top.
What are the 6 fuels obtained from industrial fractional distillation?
Refinery gas
Gasoline
Kerosene
Diesel
Fuel oil
Bitumen
What are the uses for the 6 fuels obtained from industrial fractional distillation?
Refinery gases = bottled gas
Gasoline = fuel for cars
Kerosene = aircraft fuel
Diesel = fuel for cars, lorries, buses
Fuel oil = fuel for ships, power stations
Bitumen = bitumen for roads and roofs
What is the trend in colour, boiling point, and viscosity of the main fractions?
Colour= the higher number of carbon atoms (chain length) the colour will darken.
Viscosity = the higher the number of carbon atoms (chain length) the viscosity will increase.
Boiling point = the higher the number of carbon atoms (chain length) the boiling point will increase.
What is a fuel?
A fuel is a substance that produces large amounts of energy when burned during combustion.
How do you test for carbon dioxide?
Lime water, if carbon dioxide is present it will go from colourless to cloudy.
How do you test for water?
Anhydrous copper sulfate. If water is present it will turn from white to blue.
What are the two products if complete combustion?
Water and carbon dioxide.
True of false: fuel has no impurities.
False, fuel has impurities, one of them being sulfur.
What is soot, how is it formed?
Soot is solid carbon, this is formed from incomplete combustion.
How is acid rain formed?
Cause by two acidic gases forming during combustion of hydrocarbons: nitrogen dioxide and sulfur dioxide.
They get released into the air and start to rise, then they dissolve into the rain to form acid rain.
What are the effects of soot?
Deposits of soot on buildings etc. smoke also harms our lungs.
How could we control the production of soot?
Improve supply of air (oxygen) to burning fuels. Also use of smokeless fuels.
How is carbon monoxide formed?
Incomplete combustion of fuels with carbon
What are the effects of carbon monoxide?
Carbon monoxide is a poisonous gas and limits the supply of oxygen to the blood.
What are the affects of carbon dioxide?
It is a greenhouse gas which leads to global warming.
How is sulphur dioxide formed?
Impurities in the fuel reacting with the oxygen.
How is nitrogen dioxide formed?
Nitrogen in the air reacts with oxygen when fuel releases energy to break the triple bonds in the nitrogen.
What are the effects of sulphur dioxide and nitrogen dioxide?
Acid rain.
How could you control the production of sulphur dioxide?
Remove impurities from fuels.
How could you control the production of nitrogen dioxide?
A catalytic converter,
A catalytic converter,
