Hydrocarbons Flashcards
A hydrocarbon is…
….a compound containing ONLY hydrogen and carbon
A homologous series is…
….a family of compounds with the SAME GENERAL FORMULA and SIMILAR CHEMICAL PROPERTIES
The first member of the ALKANES is…
Methane
The general formula for the alkanes is…
CnH2n+2
methane, ethane,________, butane
propane
methane + oxygen –> ? + ?
carbon dioxide + water
A functional group is…..
…the part of a molecule which gives the molecule its chemical properties
The homologous series containing a carbon carbon DOUBLE bond are the…
…alkenes
The general formula for the alkenes is…
…CnH2n
The alkene with six carbon atoms, where the C=C is between the first two carbons is called..
…hex-1-ene
A hydrocarbon containing a C=C is known as an u____________ hydrocarbon
unsaturated
To distinguish between a saturated and an unsaturated hydrocarbon we can add it to……
…bromine solution
When an alkene is added to bromine solution it….
…decolourises the solution (goes from orange->colourless)
Which other homologous series have the same general formula as the alkenes?
cycloalkanes
The cycloalkane with five carbon atoms is called…
..cyclopentane
Which will have the higher boiling point, ethane or hexane?
hexane
Why does octane have a higher boiling point than pentane?
Larger molecules have higher boiling points as there are stronger INTERMOLECULAR FORCES (attractions between molecules)
Isomers are…
…molecules with the same molecular formula but a different structural formula
The type of reaction where a small molecule adds across the double bond in an alkene is called an _____________ reaction
addition
The molecule produced when bromine undergoes and addition reaction with ethene is called..
..1,2-dibromoethane
When an alkene reacts with hydrogen, the product is an….
..alkane
Adding hydrogen across a double bond is called….
…hydrogenation
When water is added across a double bond in an alkene, the product is an…
…alcohol
The OH functional group in an alcohol is called a ___________ group
hydroxyl
Alcohols are often used as …..
..fuels and solvents
The general formula for the alcohols is..
CnH2n+1 OH
The alcohol with five carbon atoms where the OH group is on carbon 3 would be called
pentan-3-ol
ethanol + oxygen–> ? + ?
carbon dioxide + water
Which will have a higher boiling point and why..methanol or pentanol?
Pentanol will have higher b.pt as it is larger and will have stronger INTERMOLECULAR forces
Carboxylic acids contain a functional group COOH. This is called the____________ group
carboxyl
The carboxylic acid containing seven carbon atoms will be called..
..heptanoic acid
A carboxylic acid will have a pH ……
..below 7
An exothermic reaction is one which…
…releases heat energy
A reaction which takes in heat energy is known as an_____________ reaction
endothermic
In a combustion reaction something combines with ____________
oxygen
Hexene has an isomer which is not an alkene. This isomer is…..
cyclohexane
