Chemistry Test 1- S4 Flashcards
(86 cards)
What is crude oil a mixture of…
Hydrocarbon molecules
What is a hydrocarbon
A compound that contains only hydrogen and carbon atoms.
What is a way to separate crude oil into its separate fuels
Fractional distillation or distillation (boiling and condensing gases)
How does fractional distillation work
As the crude oil vapour enters the bottom of the tower and separates into its fractions (groups of molecules with similar boiling points). The higher boiling points separate at the bottom of the tower, where it is hottest and so on…. REVISE DIAGRAMM
What is a homologous series
Groups of compounds with similar chemical properties that fit a general formula
The first homologous series is the alkanes they are:
# have their carbon atoms arranged in a chain # Are saturated
What does
A= saturated
B= unsaturated mean
A= the carbon bonds are only single covalent bonds B= the carbon bonds are double covalent bonds
How do you name alkanes
Alkanes always end in -ane However the prefix is the variable: 1 carbon atom= methane 2 carbon atoms= ethane 3 carbon atoms= propane 4 carbon atoms= butane 5 carbon atoms= pentane 6 carbon atoms= hexane 7 carbon atoms= heptane 8 carbon atoms= octane
What is the molecular formula of a compound
It tells you the number of atoms of each element present in that molecule
E.g. CH4 means there are 4 hydrogen atoms and one carbon
What is a full structural formula
A drawing of the molecule when flattened out
H H H H
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H-C-C-C-C-H this is butane
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H H H HWhat is a shortened structural formula
When you take each bond one by one and write it out
CH3CH2CH2CH3
What is the general formula of alkanes
Cn H2n+2
What is an isomer
Compounds with the same molecular formula but different structural formula
How do isomers differ
They have the same number of carbon atoms in a chain but have different branch locations LOOK AT ISOMERS
What are the steps of the systematic naming of alkanes
- Find the longest chain of carbon atoms
- Number the longest carbon chain such that the branches are on the lowest number
- Indicate the position of each branch by the number of the carbon atom they are on
- Indicate the type of branch depending on the number of atoms in it (methyl, ethyl or propyl)
- Indicate the number of each type of branch
5.
Using these techniques name this
C
| -C-C-C-C-
2- methylbutane
The next homologous are the alkenes they:
# their carbon atoms are arranged in chains # they are unsaturated
How do you name alkenes
The same process as alkenes apart from the fact that they end in - ene
What is the General formula of the alkenes
CnH2n
How do you systematically name alkenes
- Find the longest chain of carbon atoms involving the c=c double bond and name it based off this
- Number the carbon atoms so that the double bond is on the lowest possible number
- Indicate the position of the double bond and add the position number to the formula
Using these techniques what is the name of this molecule:
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-C-C=C-C-
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But-2-ene
The final homologous series are the cycloalkanes and they:
# their carbon atoms are arranged in rings # the molecules are saturated
How do you name cycloaklanes
Same process as alkanes apart from the fact that you put cyclo in front of the name
What is the general formula of the cycloalkanes
CnH2n
