- Hydrocarbons are a subset of organic compounds
- Must only have hydrogen and carbon
- Organic compounds must have
- Carbon covalently bonded to hydrogen, oxygen, nitrogen, sulphur or phosphorus
- Not all carbon compounds are organic
- Calcium carbonate is not an organic compound, CO2 is not an organic compound
Isotopes: Atoms of the same element with the same number of protons but a different number of
neutrons
Relative atomic mass: weighted average of all the isotopes in relation to their abundance, over 1/12 of
carbon-12
Ionisation energy: Energy required to remove 1mol of e- from 1mol of gaseous atom
- Across the period harder to remove, increases because ENC increases because every successive
element has an additional proton. Shielding effect stays the same, atomic radius decreases
- Down the group, decreases, because shielding effect increases and ENC stays the same
Electron affinity: Energy released when adding 1mol of electron to 1mol of gaseous atom
- Across the period, ENC increases and shielding stays the same, easier to gain electrons
Homologous series
- Organic compounds can be put into families, they have their own general formula
- Families are like lists
- Eg. Alkanes: 𝐶𝑛𝐻2𝑛+2 , methane CH4, decane C10H22
- Members differ by CH2
- Successive elements change by CH2, adding CH2
- Methane CH4
- Ethane C2H6
- Propane C3H8
- Members show a gradation of physical properties
- Successively longer chains as you go down
- Will gradually increase or decrease
- For Alkanes: As you go further down, viscosity (resistance to flow) increases, density
increases, colour becomes darker
- Boiling point trends
- Affected by the length of the carbon chain
- Breaking the intermolecular force of the carbon chain, not the covalent bonds
- High mass and high area, stronger Van Der Waal forces
- High melting point and boiling point as you go down the families, because mass and area
increases and intermolecular forces become stronger and more common
- Members of a family show similar chemical properties
- Eg: all go through the same reactions
,Alkanes: Saturated (can no longer accept more carbon) homologous series of single bonded carbon
chains
- 𝐶𝑛𝐻2𝑛+2 is the general formula
- Saturated: All single bonds
- Functional group (the name of the compound in the chain that does not change, eg 1 OH in
alcohols): None
- Prefixes are based on the number of carbons
- Meth, eth, prop, but, pent, hex, hept, oct,
non, dec
- Suffix is based on homologous series name
- Condensed structural formula is easier for
drawings, makes it more simple
- You can condense the CH2’s
- Can also be empirical formula: lowest ratio
- Structural formula: Drawn diagram
- Condensed structural formula: Full formula by
position
- Molecular formula: To the left
, IUPAC naming of compounds
1. Identify the longest carbon chain (the number of carbons in the chain will give you the prefix’s
above)
2. The functional group will be the suffix
3. Identify the side chain
a. Methyl CH3
b. Pentyl C5H11
c. The location of the side group (on which number carbon) will be the number in front of
the name
d. 2-methylbutane
4. If there is more than one side group, follow alphabetical order
a. Eg. 2-chloro-3-methyl-6-methylnonane
b. Simplified: 2-chloro-3,6-dimethylnonane
For alphabetical order:
3-ethyl-4-methylbutane is correct
Not 4-methyl-3-ethylbutane
E before M
Alkenes
- Have a double bonded carbon in the chain
- Class: Alkene
- Functional group: Alkenyl
- General formula: Cn H2n
- When naming, the double bond has to be in
the longest carbon chain
- Lowest numbered carbon should be at the
double bond
- The positions of the the double bond in
alkenes affect the name of the compound
Isomer: Same molecular formula but different arrangement of the atom
You have different types of isomer, structural or positional
Alkynes
- Cn H2n-2
- Triple bonds present between carbon and carbon
- Functional group: Alkynl
- Class: alkyn
- Suffix: yne
- Must only have hydrogen and carbon
- Organic compounds must have
- Carbon covalently bonded to hydrogen, oxygen, nitrogen, sulphur or phosphorus
- Not all carbon compounds are organic
- Calcium carbonate is not an organic compound, CO2 is not an organic compound
Isotopes: Atoms of the same element with the same number of protons but a different number of
neutrons
Relative atomic mass: weighted average of all the isotopes in relation to their abundance, over 1/12 of
carbon-12
Ionisation energy: Energy required to remove 1mol of e- from 1mol of gaseous atom
- Across the period harder to remove, increases because ENC increases because every successive
element has an additional proton. Shielding effect stays the same, atomic radius decreases
- Down the group, decreases, because shielding effect increases and ENC stays the same
Electron affinity: Energy released when adding 1mol of electron to 1mol of gaseous atom
- Across the period, ENC increases and shielding stays the same, easier to gain electrons
Homologous series
- Organic compounds can be put into families, they have their own general formula
- Families are like lists
- Eg. Alkanes: 𝐶𝑛𝐻2𝑛+2 , methane CH4, decane C10H22
- Members differ by CH2
- Successive elements change by CH2, adding CH2
- Methane CH4
- Ethane C2H6
- Propane C3H8
- Members show a gradation of physical properties
- Successively longer chains as you go down
- Will gradually increase or decrease
- For Alkanes: As you go further down, viscosity (resistance to flow) increases, density
increases, colour becomes darker
- Boiling point trends
- Affected by the length of the carbon chain
- Breaking the intermolecular force of the carbon chain, not the covalent bonds
- High mass and high area, stronger Van Der Waal forces
- High melting point and boiling point as you go down the families, because mass and area
increases and intermolecular forces become stronger and more common
- Members of a family show similar chemical properties
- Eg: all go through the same reactions
,Alkanes: Saturated (can no longer accept more carbon) homologous series of single bonded carbon
chains
- 𝐶𝑛𝐻2𝑛+2 is the general formula
- Saturated: All single bonds
- Functional group (the name of the compound in the chain that does not change, eg 1 OH in
alcohols): None
- Prefixes are based on the number of carbons
- Meth, eth, prop, but, pent, hex, hept, oct,
non, dec
- Suffix is based on homologous series name
- Condensed structural formula is easier for
drawings, makes it more simple
- You can condense the CH2’s
- Can also be empirical formula: lowest ratio
- Structural formula: Drawn diagram
- Condensed structural formula: Full formula by
position
- Molecular formula: To the left
, IUPAC naming of compounds
1. Identify the longest carbon chain (the number of carbons in the chain will give you the prefix’s
above)
2. The functional group will be the suffix
3. Identify the side chain
a. Methyl CH3
b. Pentyl C5H11
c. The location of the side group (on which number carbon) will be the number in front of
the name
d. 2-methylbutane
4. If there is more than one side group, follow alphabetical order
a. Eg. 2-chloro-3-methyl-6-methylnonane
b. Simplified: 2-chloro-3,6-dimethylnonane
For alphabetical order:
3-ethyl-4-methylbutane is correct
Not 4-methyl-3-ethylbutane
E before M
Alkenes
- Have a double bonded carbon in the chain
- Class: Alkene
- Functional group: Alkenyl
- General formula: Cn H2n
- When naming, the double bond has to be in
the longest carbon chain
- Lowest numbered carbon should be at the
double bond
- The positions of the the double bond in
alkenes affect the name of the compound
Isomer: Same molecular formula but different arrangement of the atom
You have different types of isomer, structural or positional
Alkynes
- Cn H2n-2
- Triple bonds present between carbon and carbon
- Functional group: Alkynl
- Class: alkyn
- Suffix: yne
