2. Alkanes Flashcards
what atoms do alkanes contain
carbons and hydrogen atoms
what kind of hydrocarbons are alkanes
saturated
when naming alkanes what are the 2 steps for naming
- select longest chain and count # of C
- number of C determines prefix
what happens if when naming alkanes there are 2 chains of equal length
choose chain with greater number of substituents
what is the prefix for alkanes with one C
meth-
what is the prefix for alkanes with two C
eth-
what is the prefix for alkanes with 3 C
prop-
what is the prefix for alkanes with 4 C
but-
what is the prefix for alkanes with 5 C
pent-
what is the prefix for alkanes with 6 C
hex-
what is the prefix for alkanes with 7 C
hept-
what is the prefix for alkanes with 8 C
oct-
what is the prefix for alkanes with 9 C
non-
what is the prefix for alkanes with 10 C
dec-
what is the suffix for naming alkanes
-ane
what are cycloalkanes
Carbon atoms bonded in a cyclical structure
what does the prefix cyclo- indicate
the presence of a ring structure
what is the name suffix given to the substituents of alkanes
-ethyl
what end of the parent chain is labelled as the lowest number (1) if one substituent is present
the substituent is assigned the lowest number possible
what end of the parent chain is labelled as the lowest number (1) if many substituents are present
the first substituent receives the lowest number
what end of the parent chain is labelled as the lowest number (1) if many substituents are present and there is a tie
second substituent is as low as possible
what end of the parent chain is labelled as the lowest number (1) if many substituents are present and tied both times
lowest number assigned in alphabetical order
what is the prefix used to indicate that a substituent appears twice
di-
what is the prefix used to indicate that a substituent appears 3 times
tri-
what is the prefix used to indicate that a substituent appears 4 times
tetra-
what is the prefix used to indicate that a substituent appears 5 times
penta-
what is the prefix used to indicate that a substituent appears 6 times
hexa-
what are the 4 steps in naming alkanes
- identify parent chain
- identify and name substituent
- number parent chain and assign location of substituents
- arrange substituents alphabetically
what are the 2 newman projection conformation types
staggered and eclipsed
which newman projection is highest in energy and what does this mean in terms of stability
eclipsed conformation is highest in energy
means it has less stability
what 2 conformations can cyclohexane be found in
chair and boat
at any moment 99% of cyclohexane molecules are found in which conformation
chair conformation
do chair or boat conformations have more stability and energy
chair conformation has lower energy = more stability
in the chair conformation the hydrogen atoms that are in the same plane as the ring are ___
equatorial
in the chair conformation the hydrogen atoms that are perpendicular to the ring are ___
axial
what process allows the 2 conformations of each chair conformation
chair flip
what determines which chair conformation is more stable
conformation with substituent in the equatorial position is more stable as less steric interactions
what is the general formula for alkanes
CnH(2n+2)
are alkanes soluble in water
no
what are 2 reactions that alkanes undergo
combustion and substitution
what two atoms does alkanes undergo substitution with
chlorine and bromine
in what conditions can alkanes undergo substitution reactions with Br2 and Cl2
in UV light
