organic chemistry Flashcards
1
Q
what are carbon chains
A
- carbons that are covalently bonded to other carbons
- typical organic compound involves carbon atoms covalently bonded to H,O,N or a halogen (group 17)
2
Q
what is their electron configuration
A
- carbon can form 4 bonds, because of the 4 valence electrons
- 2,4
- 1S^22S^22P^2
3
Q
what is a hydrocarbon
A
- simplest organic compound that contains only C and H atoms
4
Q
what are the types of hydrocarbons
A
- aliphatics: continuous carbon chain (subcategories: alkanes, alkenes, alkynes)
- alicyclics: carbon forms a ‘ring’
- aromatics: contain a benzene ring
5
Q
explain the nomenclature of hydrocarbons
A
- number of carbons is indicated by a prefix
- 1: meth, 2: eth, 3: prop, 4: but, 5: pent, 6: hex, 7: hept, 8: oct, 9: non, 10: dec
6
Q
what is an alkane
A
- continuous straight chain molecule
- general formula: CnH(2n+2)
- saturated
- low mp and bp: weak intermolecular forces
- solubility: insoluble in polar substances, soluble in non polar substances
- states: C1-4 gas, C5-19 liquid, C20 semi solid
- nomenclature: identify number of C in longest chain by prefix, add suffix ‘ane’
- reactions: combustion (exothermic), substitution (catalyst needed, displaces H with another atom)
- note: excess halogen, then all H’s are replaced by halogen atom
7
Q
what are isomers
A
- compounds that have the same overall molecular formula, but different structural arrangement of atoms (similar chemical properties different physical properties)
- same formula different structures
- chain length can change due to chain isomers
8
Q
what are functional groups
A
- branches that come off the parent chain, several types (alkyl groups and halogens)
- alkyl groups: methyl (CH3), ethyl (CH2CH3), propyl (CH2CH2CH3)
- halogens: chloro, fluoro, bromo, iodo
9
Q
explain the nomenclature of functional groups
A
- identify longest chain, use appropriate prefix and suffix
- identify f.groups
- use numbering system to assign f.groups (lowest numbers)
- name f.groups alphabetically
- more than one of the same f.group use prefix (2: Di, 3: Tri, 4: tetra)
10
Q
what is an alkene
A
- contains a double bond between carbon atoms
- general formula: CnH2n
- unsaturated
- low mp and bp: weak intermolecular forces
- states: C2-4 gas, C5-15 liquid, C16-> semi solid
- nomenclature: similar to alkanes, but suffix is ‘ene’
- reactions: combustion, addition (halogenation, hydro halogenation, hydration and hydrogenation)
11
Q
how is halogenation useful
A
- distinguishes between alkane and alkene
- alkane: if no catalyst is present (NR), if catalyst is present (very slow)
- alkene: reaction occurs very quickly
12
Q
explain the addition reactions of alkenes
A
- addition: double bond is broken, halogen atom is added (becomes saturated)
- halogenation: halogen is added onto two new bonds
- hydro halogenation: markovinkoff’s rule, H always goes to C with most H’s, halogen goes to C with least H’s
- hydration: adding H2O, needs catalyst, nomenclature: identify parent chain length, use appropriate prefix, add ‘ol’
- hydrogenation: adding H2, heat in H2 in presence of metal catalyst
13
Q
what are cycloalkanes and haloalkanes
A
- same properties as alkanes
- haloalkanes: same properties as alkanes, has a halogen
- cycloalkane reactions: substitution (needs a catalyst, replaces H with halogen)
14
Q
what are cycloalkenes
A
- same properties as alkenes
- double bond reacts the most, easily break to form single bond
- same reactions as alkenes
15
Q
what are geometric and structural isomers
A
- geometric: double bond prevents rotation, nomenclature: cis (same side) trans (opposite sides), cis and trans used to indicate groups coming off parent chain (not H’s)
- structural: chain isomers (alkanes), positional isomers (position of double bond, must be numbered)
