Carbon Chemistry Flashcards
What are the properties of cycloalkanes?
- They are saturated hydrocarbons ( C-C single bonds)
- Insoluble
- Used for fuels and solvents
What are hydrocarbons?
Compounds that contain hydrogen and carbon only.
What is the lowest number of carbon atoms possible in a cycloalkane?
3 carbon atoms, called cyclopropane
What is a homologous series?
A family of chemicals that have similar chemical properties and the same general formula. (eg: alkanes, alkenes, cycloalkanes, alcohols, carboxylic acids).
What are alkanes?
Alkanes are a homologous series that contain carbon atoms joined together by single bonds, which are surrounded by hydrogen. They are hydrocarbons.
What is the general formula of alkanes?
CnH2n+2
What is the general formula for cycloalkanes?
CₙH₂ₙ
Are alkanes insoluble?
Yes
What is an unsaturated bond?
C to C double bond.
Name the first eight members of the alkane series.
Methane CH₄, ethane C₂H₆, propane C₃H₈, butane C₄H₁₀, pentane C₅H₁₂, hexane C₆H₁₄, heptane C₇H₁₆, octane C₈H₁₈.
In homologous series’, what happens to the melting / boiling point as the size of the molecule increases?
As the size of the molecule increases, the melting / boiling point increases.
What are isomers?
They have the same molecular formula but a different structural formula.
(eg: butane C₄H₁₀ and 2-methylpropane C₄H₁₀)
What are the properties of alkenes?
- Unsaturated hydrocarbons (contains at least one double bond between carbon atoms)
- Names end in -ene
- Double bond can be anywhere in the carbon chain
- Insoluble in water
- Can be used to make polymers and alcohols
What is the general formula of the alkenes?
CₙH₂ₙ
How do you name branched alkanes?
1) Draw out full structural formula.
2) Look for longest chain of carbon atoms.
3) Which side is the branch closest to and call the starting carbon C₁.
4) Give the other carbons in the chain positions.
5) See what position the branch is on and give a prefix.
If there is 1 C in the branch, methyl
2 C in the branch, ethyl etc.
What is the name of this branched alkane: CH₃CH(CH₃)CH₂CH(CH₃)CH₂CH₃.
2, 4 - dimethylhexane
Name the first 3 members of the cycloalkanes series
Cyclopropane - C₃H₆
Cyclobutane - C₄H₈
Cyclopentane - C₅H₁₀
How do you name alkenes?
1) Look for the longest continuous chain - name it after the corresponding alkane, (eg: ethane, but-1-ene) etc
2) Give the double bond a position, eg: position 2
3) The position of the double bond goes inside the name, eg: pent-2-ene
4) If a branch is present, give it a position from the side the double bond is closest to.
How can you tell an alkene apart from an alkane / cycloalkane?
You test for unsaturation.
An alkene decolourises bromine water.
Bromine water remains red / orange when placed into an alkane / cycloalkane.
What is a polymer?
A very long chain molecule, made up of thousands of smaller molecules, called monomers.
Monomers are alkenes.
How do you name a polymer?
Put the word ‘poly’ in front of the monomer’s name.
eg: ethene → (poly)ethene
vinylchloride → (poly)vinylchloride
How do monomers react?
Addition polymerisation
How do you draw a section of a polymer?
- Draw three monomers.
- Move the side atoms so they line up vertically.
- Connect them and add side bonds with brackets at the ends.
What does it mean when alkenes are unsaturated?
More atoms can be added to them
What are the 3 addition reactions?
- alkene + hydrogen —> alkane
- alkene + halogen —> dihaloalkane
- alkene + water —> alcohol