Chapter 4.1- 4.4 Flashcards
(21 cards)
Cycloalkanes are… and what is the formula for them?
they are alkanes that arranged in a carbon ring they have two fewer hydrogens than alkanes and have the formula of CnH2n.
What is the general rule and shape of carbon atoms in alkane and cycloalkane structures?
a tetrahedral with a sp3 hybridization
Why are butane and pentane called straight chain structures? and what is the better term for it
the carbon atoms are connected from left to right. A better term for this is called unbranched, meaning that every carbon atom is bonded to two or less carbon atoms (only include primary and secondary carbon atoms)
What are the constitutional isomers of C4H10?
Butane and isobutane
What are the constitutional isomers of C5H12?
Pentane, isopentane, and neopentane
What are constitutional isomers?
molecules that have the same chemical formulas but different in the way they are bonded to each other.
they have different physical properties.
Does the number of possible constitutional isomers increase/decrease as you add more carbons to a compound?
increases
What is the ending name for all alkane groups?
ane
What are the rules for naming unbranched alkyl groups
- when a hydrogen atom is removed from a molecule replace the ending with alkyl
- Pre-fix of the name
1 carbon atom= methane
2 carbon atom= ethane
3 carbon atom= propane
4 carbon atom= butane
How to name branched alkane chains?
- located the longest hydrocarbon chain
- count the number of carbons starting on the side closest to the branch
- The number is placed first than # of subsistent than the parent name ( derived from the longest hydrocarbon chain)
How to name branched alkane chains when two subsistent are present?
give each substituent a number
corresponding to its location on the longest chain.
The number is based on which is the closest that being first and the next being second
You write it in alphabetical order
How to name branched alkane chains when two substituents are present on the same carbon atom?
use that number twice but right the # of subsistent in alphabetical order
How to name branched alkane chains when substituents are identical?
indicate this by the use of the
prefixes di-, tri-, tetra-, and so on come after the numbers and comas
How to name branched alkane chains when two chains of equal length compete for selection as the parent chain?
choose the chain with the greater number of substituents:
How to name branched alkane chains when branching first occurs at equal distance either end of the chain?
choose the name that gives the lower number at the first point of difference:
What are the two groups that can be derived from propane and how?
Propyl group: derived by removal of a terminal hydrogen
isopropyl group:
is derived by removal of a hydrogen from the central carbon
What are the four c4 carbon groups? and how are they attached? Draw them out
Butyl
Isobutyl
sec-butyl
tert-butyl
they are a subsisent group attached to the hydrocarbon chain
How to classify hydrogen atoms?
Hydrogen atoms determined by the primary secondary or tertiary carbon they are attached to and are labeled the same way
How to name halo alkyls?
When the subsistent are at different distances : you name the nearest one first if its a halogen then number order first, then the number name assigned of the other
when the subsistent are equal length: you right from left to right.
How to name halo alkyls?
When the subsistent are at different distances : you name the nearest one first if its a halogen then number order first, then the number name assigned of the other
when the subsistent are equal length: you right from left to right.
