3. Organic Chemistry Flashcards
Nomenclature rules:
- find longest main chain
- number from side that will give lowest number
- name alphabetically
- if more than one same side chain: di, tri, tetra
- priority to closest to C=C bond
What is a homologous series
- Families of organic compounds with the same general formula
- show a gradual change in physical properties
- each member defers by CH2 from the last
- similar chemical properties
What is a functional group
an atom or group of atoms which when present in different molecules causes them to have similar chemical properties
What is an isomer
molecules with the same molecular formula but different arrangements of atoms
structural isomerism
molecules with the same molecular formula but different structural formula
Why does a branch isomer (X) have lower boiling point than unbranched (Y)
- Molecule X is branched whereas molecule Y is unbranched
- Molecule Y is more compact
- Molecule X has smaller surface area of contact
- molecule X has weaker VdW forces between the molecules
Describe structural isomerism: chain
- Caused by different arrangements of carbon skeleton
- similar chemical properties
- slightly different physical properties
Describe positional structural isomerism
- Each molecule same carbon skeleton
- same functional group
- but functional group in different position
- similar chemical properties
- different physical properties
sigma bonds
allow free rotation
why do alkenes exhibit EZ isomerism
- restricted rotation around C=C bond
- atoms attatched to e/ carbon fixed in place
why do alkenes exhibit EZ stereoisomerism?
there is no free rotation around a C=C bond
* atoms attatched to each carbon are in fixed position
general formula of cycloalkene
CₙH₂ₙ-₂
a functional group isomer of an alkene MUST BE
a cycloalkane
for nonmenclature ALWAYS
number from side that gives lowest number for substituents
