Chapter 10: Organic Chemistry Flashcards
Distinguish between:
- Empirical formula
- Molecular formula
- Full structural formula
- Condensed structural formula
- Skeletal formula
- Empirical formula: simplest whole number ratio of the elements present in a compound
- Molecular formula: Total number of atoms of each element present in a compound (integer multiple of the empirical formula)
- Full structural formula: Shows all the atoms and bonds in a molecule
- Condensed structural formula: Simplest representation of how atoms are arranged in a molecule
- Skeletal formula: Shorthand representation of a molecule and its geometry (lines to represent bonds, angles to represent C atoms, and H atoms are assumed)
Explain what alkanes are
- Family of hydrocarbons
- General formula: CₙH₂ₙ₊₂
Define:
- Homologous series
- Functional group
Homologous series: Series of compounds with the same functional group, where one member differs from the next by a fixed structural unit (CH₂/mR=14)
- Members of the same homologous series: Have similar chemical properties and display a gradation in physical properties (MP/BP/solubility)
Functional group: Atom/group of atoms that gives a compound it is characteristic chemical properties (reactive part of the molecule)
Identify functional groups of:
- Alkanes
- Alkenes
- Alkynes
- Alcohols
- Ethers
- Aldehydes
- Ketones
- Carboxylic acids
- Esters
- Nitriles
- Amines
- Amides
- Alkanes: NIL (alkyl)
- Alkenes: C=C (alkenyl)
- Alkynes: C≡C (alkynyl)
- Halogenoalkanes: –Br/CI/I (halo)
- Alcohols: –OH (hydroxyl)
- Ethers: C–O–C (ether)
- Aldehydes: CH=O (carbonyl)
- Ketones: C=O (carbonyl)
- Carboxylic acids: COOH (carboxyl)
- Esters: COOC (ester)
- Nitriles: C≡N (nitrile)
- Amines: NH₂/NHR/NR₂ (amino)
- Amides: C=O(NH₂) (carboxamide)
State the molecular formula of benzene, draw its shape, name its functional group and state the term used to describe compounds containing/not containing a benzene ring
Benzene: C₆H₆ (phenyl functional group)
- Shape: Planar hexagonal ring with 6 Cs, 1 H atom attached to each
- Compounds containing a benzene ring: aromatic
- Compounds not containing a benzene ring: aliphatic
Explain trends in boiling point within a homologous series
Boiling points can only be compared within a homologous series, and not between series
- B.P increases along a series: higher mR = stronger LDF between molecules
- Alcohols have a higher B.P and greater solubility in water than alkanes: ability to form hydrogen bonds between alcohol molecules (B.P) and with water molecules (solubility)
Use IUPAC rules to name alkanes
- Assign prefix using longest carbon chain
- Use suffix “-ane” to indicate alkane
- Identify substituent groups/multiple identical substituent groups
- Assign substituent groups lowest possible number
- Arrange names of substituent groups in alphabetical order
Eg. 3,3,4-trimethylhexane
Distinguish between saturated and unsaturated compounds
Saturated compounds: contain only single bonds (alkanes)
Unsaturated compounds: contain double/triple bonds (alkenes and alkynes)
Use IUPAC rules to name alkenes and alkynes
- Indicate position of functional group by assigning lowest possible number in format “alk-x-ene”/”alk-x-yne”
(*lowest number assigned to functional group, not substituent group) - Add extra “a” if there are multiple functional groups present
Eg. 4-methylpent-2-ene
Eg. hexa-1,3,5-triene
Use IUPAC rules to name halogenoalkanes
- Indicate type and position of halo functional group in format “x-haloalkane”
(*lowest number assigned to functional group/substituent group according to alphabetical order)
Eg. 2-bromo-3-chloropentane
2-bromo-5-methylhexane
Use IUPAC rules to name alcohols
- Indicate position of –OH functional group in format “alkan-x-ol”
(*Lowest number assigned to functional group)
Eg. 5-methyl-hexan-3-ol
Use IUPAC rules to name ethers
- Name shorter carbon chain as a substituent group (methoxy-, ethoxy, propoxy, etc.)
Eg. 2-ethoxy-2-methylbutane
Use IUPAC rules to name aldehydes
- Carbon containing the functional group is C₁
- Format: “alkan-al”
Eg. 3-methyl-butanal
Use IUPAC rules to name ketones
- Indicate position of by assigning lowest number to functional group in format “alkan-x-one”
Eg. 4-methyl-pentan-2-one
Use IUPAC rules to name carboxylic acids
Carbon containing the functional group is C₁
- Format: “alkanoic acid”
Eg. 2,3-dimethylbutanoic acid
Eg. butanedioic acid