Fuels And Heats Of Reactions Flashcards
Organic chemistry
The study of the compounds of carbon
Hydrocarbon
A compound that contains carbon and hydrogen only
Fossil fuels
Fuels that were formed from the remains of plants and animals that lived millions of years ago
Saturated compound
One in which there are only single bonds between the atoms in the molecule
Homologous series
A series of compounds of similar chemical properties
Showing gradations in physical properties
Having a general formula for its members
Each member having a similar method of preparation
Each member differing from the previous member by a unit
Unsaturated compound
One that contains one or more double or triple bonds between the atoms in the molecule
Aliphatic compound
An organic compound that consists of open chains of carbon atoms and closed chain compounds that resemble in chemical properties
Aromatic compounds
Compounds that contain a benzene ring structure in their molecule
Fractions
Refinery gas Petrol Naphtha Kerosene Diesel oil Lubricating oil Fuel oil Bitumen
Auto-ignition
Premature ignition of the petrol air mixture before normal ignition of the mixture by a spark takes place
Octane number
A measure of the tendency of the fuel to resist knocking
Catalytic cracking
The breaking down of long-chain hydrocarbon molecules by the action of heat snd catalysts into short-chain molecules for which there is greater demand
Heat of reaction
The heat change when the numbers of moles of reactants indicated in the balanced equation for the reaction react completely
Heat of combustion
The heat change when one mole of the substance is completely burned in excess oxygen
Kilogram calorific value
The heat energy produced when 1 kg of the fuel is completely burned in oxygen
Bond energy
The average energy required to break one mole of a particular covalent bond and to separate the neutral atoms completely from each other
Heat of neutralization
The heat change when one mole of H+ ions from acid reacts with one mole of OH- ions from a base
Heat of formation
The heat change that takes place when one mole of a compound in its standard state is formed from its elements in their standard states
Hess’s Law
If a chemical reaction takes place in a number of stages the sum of the heat changes in the separate stages is equal to the heay change if the reaction is carried out in one stage
Law of Conservation of Energy
Energy cannot be created or destroyed but can only be converted from one form of energy into another
Ethene
C2H4
Propene
C3H6
Butene
C4H8
Cyclohexane
C6H12
Ethyne
C2H2
Benzene
C6H6
Methybenzene
C7H8
Ethylbenzene
C8H10
MTBE
Methyk tertiary butyl ether
Methanol
CH3OH
Ethanol
C2H5OH
Methyl
CH3
Ethyl
C2H5
Propyl
C3H7
Butyl
C4H9
Formula for alkane chemical formula
Cn H2n+2
Alkyl formula
CnH2n+1
Methyl Tertiary Butane Ether
An oxygenate to increase a hydrocarbon’s octane number
Give ruse to pollution give cleaner emissions
Factors that influence the octane number
Length of the chain- the shorter the chain the higher the octane number
Branching - more branches higher octane number
Strcutures- cyclic structure compounds have higher octane numbers
Methods of increasing octane numbers
Isomerisation
Catalytic cracking
Dehydrocyclisation
Adding oxygenates
Isomerisation
Changing straight chained hydrocarbons into gheir isomers
Heated with a catalyst to break the chains
The chain fragments join to change its structure
Dehydrocylisation
Removing the hydrogen atom in a hydrocarbon and turning it into a cyclic structure with the help of a catalyst
Methods of manufacturing hydrogen
Steam reforming of natural gases
Electrolysis of water
