Unit 17- organic chemistry Flashcards
What is in petroleum
Mixture of different organic compounds
What are hydrocarbons
Compound that contain only carbon and hydrogen
What is a structural formula
the formula of a compound displayed to show bonds between the atoms as lines
How we use petroleum
Fuel
Give the order of a fraction of petroleum
Refinery gas ---- ( retarded) Gasoline ----( girl ) Naphtha ---- ( no ) Kerosene / paraffin ---- (kock / penis) Diesel oil ( dick ) Fuel oil ( fck ) Lubricating oil ( life) Bitumen ( beach )
Uses of fraction of petroleum
refinery gas - for cooking and heating gasoline - fuel for cars naphtha - making chemicals kerosene - jett fuel diesel oil - fuel for diesel engines fuel oil - fuel for power station lubricating fraction - oil for car engines bitumen - for road surfaces
The trends the fraction of petroleum show
the larger the molecules in a hydrocarbon
- higher boiling point
- less volatile ( less likely to evaporate)
- more viscous ( less easily it will flow)
- less easily it will burn
What does cracking means
reaction in which long-chain hydrocarbon molecules are broken down to shorter molecules
Is cracking hydrocarbon a thermal decomposition
yes
Product of cracking ethane and its condition
the product- ethene and hydrogen.
condition- above 800 degrees celsius with steam
Properties of homologous series
All the compounds fit in the same general formula
The chain length increases by 1 each time
As the chain gets longer, the compounds show a gradual change in properties
The general formula for an alkane
C(n) H(2n+2)
Why alkanes are saturated
they only contain carbon-carbon single bond
Methane reacts with chlorine to form chloromethane in the presence of light. What kinds of reactions are happening
Substitution reaction, photochemical reaction
What are isomers
Compounds with the same formula but different structures
Uses of alkanes
fuels
The general formula for alkenes
C(n)H(2n)
Why are alkenes unsaturated
They contain carbon-carbon double bond
First four members of alkane
methane, ethane, propane, butane
First three members of the alkene
ethene,propene, butene
Why are alkenes much reactive than alkanes
alkenes contain double carbon bond
The condition of reaction between ethene and hydrogen to form ethane
150 degree celcius, catalyst nickel
The condition of reaction between ethene and water to form ethanol
300 degrees celcius, 60 atm, catalyst conc. phosphoric acid
Test for unsaruration
Add bromine water to the hydrocarbon. If the hydrocarbon is unsaturated then bromine water will change colour from orange to colourless.
general formula for alcohol
C(n)H(2n+1)OH
First four members of the alcohol
methanol,ethanol,propanol,butanol
Uses of alcohol
Perfumes, fuel
What is fermentation
The process in which the enzymes in yeast break down sugars, to form ethanol and carbon dioxide
When do the yeast stop working during fermentation
when the % of ethanol reaches a certain level, or if the mixture gets too warm
How is ethanol separated from the fermentation
fractional distillation
general formula for carboxylic acid
C(n)H(2n)O2
First four members of carboxylic acids
methanoic acid, ethanoic acid, propanoic acid, butanoic acid
Two ways to make ethanoic acid
(acid) fermentation, oxidation
What happens during acid fermentation
ethanol is oxidised by bacteria to form ethanoic acid
What can be the oxidising agent for making ethanoic acid from ethanol
Acidified potassium manganate (vii)
Why is ethanoic acid acidic
It contains H+ ions
How are esters form
Ethanoic acid reacts with alcohols to form esters
what is the two product in complete combustion
carbon dioxide and water
