Chem Exam Unit 2:

• Organic Compounds:
• Organic Compounds:

  • Compounds that are mainly carbon and hydrogen bonded together.
  • Can also contain nitrogen, oxygen, sulfur, phosphorous, or any halogen.
• Inorganic Compounds: Compounds that do not contain carbon.

  • May contain carbides, carbonates or oxides of carbon.
• Organic Chemistry: Branch that studies the structure, properties and reactions of chemical compounds consisting primarily of carbon and hydrogen.
• Importance of Carbon:

  • Carbon has 4 valence electrons, allowing for four bonds to be formed from one carbon.
  • Carbon atoms can form many geometrical structures (straight chains, branched chains, rings, sheets, tubes, spheres)
  • Carbon can form single, double, or triple bonds.
  • Millions of different compounds can be formed.
• Isomers: Molecules that have the same molecular formula but different structural formula. Occurs because of carbon atom's ability to make a variety of shapes.
• Constitutional Isomers: Molecules with different connectivity

  Ethanol and Dimethyl Ether
• Stereoisomers: Molecules with same connectivity but different orientation of atoms in space.

  • Cis stereoisomers where hydrogen and carbon are on separate planes and trans stereoisomers where carbon and hydrogen are on the the same plane.

  Diastereomers: Stereoisomers based on a double bond.

  Enantiomers: Stereoisomers where molecules are mirror images of each other around a single carbon bonded to 4 different functional groups.
• Structural Isomers: Compound with same molecular formula as another compound but a different structure (hexane and 2-methylpentane)
• Hydrocarbons: Simplest organic compounds

  Contain only hydrogen and carbon

  • Alkanes: atoms bonded together by single bonds
  • Alkenes: atoms bonded together with at least one double bond
  • Alkynes: atoms bonded together with at least one triple bond
• Functional Group: Largest priority group in an organic compound
• Substituents: Hydrogens on a carbon chain replaced by other lower priority atoms eg. (halogen atoms). Numbered after functional group.
• Properties of Alkanes:

  • Gas/Liquid State at room temperature
  • Melting/Boiling point increases as number of carbons in chain increases
  • Relatively low boiling/melting points
  • Branch has lower boiling/melting point as less LDF present
  • Hydrophobic: Like dissolves Like
• Properties of Alkenes:

  • Gas or Liquid state at room temperature
  • As number of carbons in chain increases, boiling/melting point increases
  • Lower boiling/melting points than alkanes; double bond is not rigid and decreases LDF
  • Location of double bond affects boiling point
  • Hydrophobic: Like dissolve Like
• Properties of Alkynes:

  • Various states: gas, liquid, solid based on molecular size
  • Higher boiling points than alkenes and alkanes because of rigid triple bond.
  • Hydrophobic
  • Soluble in non-polar solvents.
• Cyclic: Hydrocarbon chains that form rings. Cyclo proceeds root name.

  Double/Triple bonds must occur on first carbon atom in the ring.
• Aromatic Hydrocarbon: Hydrocarbons that contain benzene that often have a strong odour.

  Benzene alternates in two resonance forms as the p orbitals are delocalized throughout the entirety of the molecule.
• Properties of Cyclics:

  • Varies in state based on size of carbon ring.
  • Higher boiling/melting points compared to acyclic counterparts based on absence of terminal ends and branching, + reduced surface area (exceptions with smaller rings.)
  • Hydrophobic aside from cyclopropane
  • Soluble in hydrocarbons, ethers, and chlorinated solvents.
• Aromatic Properties:

  • Non-polar
  • Hydrophobic-used as solvents for other organic compounds
  • Rings are chemically stable and remain intact during chemical reactions
  • Higher melting/boiling points to aliphatic compounds of similar molecular weight
• Carbon:

  • good conductor of heat/electricity
  • Six Protons and Six Electrons
  • Can be made artificially and forms diamonds
• Hydrocarbon Derivatives: Hydrocarbons with functional groups bonded to them

  Derivatives are identified by the functional group they contain
• Halocarbons:

  • Elements from group 17 (halogens), join a carbon atom in place of a hydrogen
  • Halogen's name changes slightly: bromo, chloro, iodo, fluoro
• Properties of Halocarbons:

  • Low Boiling points
  • Denser than air
  • Generally insoluble in water
• Alcohols: Organic compounds containing a hydroxyl functional group

  • Primary Alcohol: OH group bonded to a carbon bonded to one other carbon
  • Secondary Alcohol: OH group bonded to a carbon bonded to two other carbons
  • Tertiary Alcohol: OH group bonded to a carbon bonded to three other carbons
  • Methanol: Bonded to no other carbons
• Properties of Alcohols:

  • Colourless liquid at room temperature (12 carbons or less)
  • Higher boiling points than alkanes because of hydrogen bonding between adjacent hydroxyl groups
  • Alcohols with up to 4 carbons on parent chain are more soluble in water
  • As carbon chain increases, solubility decreases
  • Alcohols dissolve polar and nonpolar solvents.
• Ethers: Organic compounds that have an oxygen attached to two hydrocarbon chains.
• Properties of Ethers:

  • Higher boiling points than alkanes, lower than alcohols (dipole-dipole vs hydrogen bonds)
  • Slightly soluble in water: polar molecule
• Aldehydes: Formyl group (double bonded oxygen) located at end of carbon chain

  • Aldehydes cannot be cyclic as formyl group is always on carbon one
• Ketones: Contain carbonyl functional group (oxygen with double bond to carbon)

  • Carbonyl group found on interior of carbon chain
• Properties of Aldehydes and Ketones:

  • Polar molecules allowing for dipole-dipole forces
  • Lower boiling points than alcohols
  • More soluble than alkanes, less soluble than alcohols. Solubility decreases as carbon chain increases.
• Carboxylic Acids: Contain a carboxyl functional group

  Carboxyl group found at carbon #1
• Properties of carboxylic acids:

  • Weak acids
  • React with bases to form ionic compounds and water
  • Very soluble when 5 or less carbon atoms are present based on carboxyl and hydroxyl groups present
  • Highest melting/boiling points
• Esters: Contain a carboxyl group bonded to a second oxygen atom bonded to another carbon atom.

  Responsible for artificial smells
• Amines: Nitrogen attached to one or more alkyl groups

  • Primary Amines: Alkan-n-amine Location of NH2 groups
  • Secondary Amines: N-Alkyl-Alkan-N-amine to id secondary carbon chain
  • Tertiary Amines: N-Alkyl-N-Alkyl-Alkan-n-amine to id both chains
• Amides: Similar to an ester, except the second oxygen atom replaced by a nitrogen atom.

  • Primary Amide: Alkane +Amide
  • Secondary Amide: N-Alkyl-Alkane-amide
  • Tertiary Amide: N-Alkyl-N-Alkyl-Alkane-amide
• Addition Reaction: Atoms are added to an unsaturated molecule (alkene/alkyne)

  Products should have less carbon-carbon bonds
• Halogenation: A reaction in which a halogen halide is added to an organic molecule

  • Monosubstituted: Hydrogen halide added
  • Disubstituted: Diatomic halogen added
• Bromine: Can be used to test saturation of unknown organic molecule

  • Saturated: solution will be orange (bromine's colour)
  • Unsaturated: solution will be colourless
• Hydrogenation: Hydrogen added to alkyne/alkene

  Usually includes a transition metal catalyst

  Produces alkane

  Known as a redox reaction
• Hydration/Hydrolysis: Occurs when water is added to an alkene.

  • Strong acid is a catalyst
  • Creates water and an alcohol