Organic Chemistry Paper 2 Flashcards
What is a hydrocarbon
Compounds that only contain hydrogen and carbon
What is crude oil
The remains of dead organisms that lived millions of years ago
What is crude oil an important source of
Fuel and feedstock
What is crude oil an important source of
Fuel and feedstock
What is the general formula for alkanes
CnH2n+2
What are the first 4 alkanes you need to know
Methane
Ethane
Propane
Butane
Are alkanes saturated or unsaturated hydrocarbons
Saturated as it’s a single bond
Describe the process of fractional distillation
First heat the crude oil. heated crude oil enters a tall fractionating column which is hot at the bottom and gets cooler towards the top. vapours from the oil rise through the column vapours condense when they become cool enough. liquids are led out of the column at different heights
Why do small hydrocarbon molecules have low boiling points
They have weak intermolecular forces that don’t require a lot of energy to overcome
What is viscosity
A measure of how difficult it is for the substance to flow- higher viscosity means it’s more thick
What properties do smaller hydrocarbons have
Boiling points below room temperature
Very flammable
Low viscosity
What properties do larger hydrocarbons have
High boiling point (above room temperature)
Difficult to ignite
High viscosity
When does complete combustion occur
When there is a good supply of air(oxygen)
Is complete combustion exothermic or endothermic
Exothermic
What is the word formula for complete combustion
Hydrocarbon +oxygen —-> carbon dioxide +water
What is the word equation of incomplete combustion
Hydrocarbon + oxygen——-> carbon monoxide + water