Organic chemistry Flashcards
Describe what crude oil is and where it comes from, including the basic composition of crude oil and the general chemical formula for the alkanes
Crude oil - a mixture of many hydrocarbons found in rocks and formed from dead plants and animals that have spent millions of years buried in mud.
Alkanes - CnH2n+2
State the names of the first four members of the alkanes and recognise substances as alkanes from their formulae
Methane, Ethane, Propane and Butane.
CH4, C2H6, C3H8, C4H10
Describe the process of fractional distillation, state the names and uses of fuels that are produced from crude oil by fractional distillation
Fractional distillation - a process used to separate the hydrocarbons in crude oil into fractions according to their boiling points.
Describe trends in the properties of hydrocarbons, including boiling point, viscosity and flammability and explain how their properties influence how they are used as fuels
As the length of the hydrocarbons chain increases the, boiling point and viscosity increase and the flammability decreases.
Hydrocarbons are used as fuels because combustion releases a lot of energy.
Describe and write balanced chemical equations for the complete combustion of hydrocarbon fuels
Complete combustion - an oxidation reaction that occurs when a fuel reacts with plenty of oxygen
hydrocarbon + oxygen → carbon dioxidde
Describe the process of cracking and state that the products of cracking include alkanes and alkenes and describe the test for alkenes
Complete combustion - an oxidation reaction that occurs when a fuel reacts with plenty of oxygen
hydrocarbon + oxygen ⇢ carbon dioxide + water
CH4 + 2O2 ⇢ CO2 + 2H2O
Balance chemical equations as examples of cracking when given the formulae of the reactants and products
long-chain alkane ⇢ shorter-chain alkane + alkene
Explain why cracking is useful and why modern life depends on the uses of hydrocarbons
