Alkanes and Conformational Isomers of Alkanes Flashcards
What are alkanes? What is the formula?
Compounds with C-C and C-H single bond.
Cn H2n+2
What is the formula for methane
C1H4
What is the formula for ethane?
C2H6
What is the formula for propane?
C3H8
What is the formula for butane?
C4H10
What is the relationship between an alkane’s size and its boiling point and melting point?
boiling point and melting point increase as size of alkane increases directly proportional to the increase in dispersion force
IN ISOMERS:
more branched means less surface area means less boiling point for isomers
What is the parent chain name for C1H4
meth
What is the parent chain name for C2H6
Eth
What is the parent chain name for C3H8
Prop
What is the parent chain name for C4H10
But
What is the parent chain name for C5H12
Pent
What is the parent chain name for C6H14
Hex
What is the parent chain name for C7H16
Hept
What is the parent chain name for C8H18
Oct
What is the parent chain name for C9H20
Non
What is the parent chain name for C10H22
Dec
What is a straight chain alkane?
Carbon atoms connected to no more than 2 other carbons
- continuous chain
Ex: butane and pentane
What is a branched like alkane?
carbon atoms connected to 3 or 4 carbon atoms
Ex: isobutane and isopentane
What are alkyl group?
Partial structure that remains after the removal of one H from an alkane
- parts of a larger molecule
What is the name replacement at the end of an alkyl group?
“ane” ending of alkane with “-yl” ending
Ex: methane (CH4) to methyl (CH3-)
Why is rotation possible around C-C bond in alkanes?
Alkanes are cylindrically symmetrical
What is a confirmation?
Different arrangements of atoms that results from bond rotation
Which configuration is the most stable?
Staggered Confirmation
The confirmation that position all six C-H in an ethane as far away from one another as possible;
- lowest energy
Which configuration is the least stable?
Eclipse Confirmation
The confirmation in which all six C-H bond in an enthane are as close as possible
- highest energy