Organic AS Power Point

• Molecular Formula: Shows the actual number of atoms of each element in a compound
• Compound: Ethane

  Molecular Formula: C2H6

  No. of Atoms Present: 2 carbon atoms, 6 hydrogen atoms
• Compound: Chloropropane

  Molecular Formula: C3H7Cl

  No. of Atoms Present: 3 carbon atoms, 7 hydrogen atoms, 1 chlorine atom
• Compound: Ethanoic Acid

  Molecular Formula: C2H4O2

  No. of Atoms Present: 2 carbon atoms, 4 hydrogen atoms, 2 oxygen atoms
• Empirical Formula: The simplest whole number ratio of each element in a compound
• Compound: Ethane

  Molecular Formula: C2H6

  Empirical Formula: CH3
• Compound: Chloropropane

  Molecular Formula: C3H7Cl

  Empirical Formula: C3H7Cl
• Compound: Ethanoic Acid

  Molecular Formula: C2H4O2

  Empirical Formula: CH2O
• General Formula: Algebraic formula that can describe any member of a homologous series
• Homologous Series: Alkanes

  General Formula: CnH2n+2
• Homologous Series: Alkenes

  General Formula: CnH2n
• Homologous Series: Halogenoalkanes

  General Formula: CnH2n+1X (X = halogen)
• Homologous Series: Alcohols

  General Formula: CnH2n+1OH
• Displayed Formula: Shows how all atoms and all the bonds are arranged
• Structural Formula: The arrangement of atoms in a molecule, carbon by carbon, with attached hydrogens and functional groups
• Compound: Butanoic Acid

  Structural Formula: CH3CH2CH2COOH
• Compound: 3,3-dimethylpentane

  Structural Formula: CH3CH2C(CH3)2CH2CH3
• Skeletal Formula: Shows just the carbon skeleton, with hydrogen atoms removed and functional groups present
• Nomenclature Rules:

  <|>Rule 1: Count the number of carbon atoms in the longest unbranched chain to determine the stem
• Rule 2: Identify any side groups and add the prefix before the stem as part of the name
• Rule 3: The suffix depends on the functional group
• Rule 4: All substituent groups are named alphabetically
• Rule 5: If there's more than one substituent group, use di-, tri-, tetra- as prefixes
• Rule 6: Each substituent group needs a number to indicate its position on the carbon chain
• Rule 7: Dashes are put between numbers and letters
• Isomers occur when molecules with the same molecular formula have different arrangement of atoms
• Structural Isomerism: Compounds with the same molecular formula but different structural formulae

  <|>Chain Isomers: Different ways of arranging the carbon chain
• Position Isomers: Same carbon chain but functional group bonded to different carbons
• Functional Group Isomers: Same molecular formula but different functional groups
• Stereoisomerism: Same structural and molecular formula but different arrangement of atoms in 3D space
• 1. Z Isomers Criteria:

  <|>Carbon-carbon double bond must be present

  <|>Each carbon in the double bond must be attached to two different groups
• 1. Z Isomers Identification:

  <|>Look at the priority of the groups attached to the first carbon with the double bond

  <|>Use CIP priority rules to determine E or Z isomer
• 1. Z Isomers Example:

  <|>Compound: But-2-ene

  1. Z Isomers:

  <|>Z Isomer: CH3 groups on the same side

  Name: Z-but-2-ene
• E Isomer: CH3 groups on different sides

  Name: E-but-2-ene
• Petroleum is separated into simpler mixtures (fractions) based on their boiling point ranges
• Fractional distillation of crude oil involves passing petroleum vapour into a fractionating column with a temperature gradient
• Different chain lengths and boiling points cause each fraction to condense at different temperatures in the column
• Larger hydrocarbons in petroleum with high boiling points are collected at the bottom of the column
• Smaller hydrocarbons with low boiling points are collected at the top of the column as gases
• Cracking is used to break down large alkanes into smaller, more useful molecules