Naming organic compounds Flashcards
What is the order of alkanes and what are their formulas?
methane - CH4
ethane - C2H6
propene - C3H8
butane - C4H10
pentane - C5H12
hexane - C6H14
heptane
octane
non
dec
What is the general formula for alkanes?
Cn H2n + 2
Define isomers
molecules with the same chemical formula but diff structures
Define structural isomers
- molecules with same molecular formula
- but diff structural formula
Define chain isomers
- molecules with same molecular formula
- but diff displayed formula
What are the steps to naming branched alkanes?
- find the longest chain - name as usual
- find any side chains - name them by looking at the positions (use prefixes for number of carbon atoms + end in yl)
- the side branches are the same use:
- di = 2
- tri = 3
- tetra = 4
- penta - 5
- hexa = 6
- hepta = 7
- octa = 8
Define functional group isomerism
- molecules with same molecular formula
- but diff functional groups
Define positional isomers
- molecules with same molecular formula
- with functional groups on diff positions in molecule
What is the general formula for alkenes?
Cn H2n
What is the order of alkenes and what are their formulas?
ethene - C2H4
propene - C3H6
butene - C4H8
pentene - C5H10
hexene - C6H12
heptene
octene
nonone
decene
What type of bonds do saturated alkanes have?
C - C single bond
What type of bonds do unsaturated alkenes have?
C = C double bond
What are E - Z isomers?
If you have 2 diff groups attached to a C of C=C in alkenes, this is an E - Z isomer
What is it called if the E-Z isomers are on the same side?
CIS
What is it called if the E-Z isomers are on opposite sides?
TRANS
View booklet to see how to name alkenes + dienes
page 11 and12
How do you name cycloalkanes and cycloalkenes?
- count the carbon atoms
- name the alkene
- add cyclo onto beginning of name
Define stereoisomers
- molecules with the same structural formula
- but different arrangement of atoms in space
why do stereoisomers occur?
restricted rotation around C = C give rise to cis (Z) / trans (E)
Describe the reactivity of alkenes vs alkanes
- C=C (alkenes) is stronger than C - C
- sigma bond is stronger than pie bond
- C = C contains sigma and pie bond, C - C contains just sigma bond
- alkenes are more reactive as they have double bonds
What are the names of the multipliers used when more than one side chain is the same
Di
Tri
Tetra
Penta
Hexa
Hepta
Octa
