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Overall test review
Alkanes
What is an alkane?
Fully saturated carbon chain; only single bonds
How do you name alkanes?
1. find longest carbon chain
2. add –ane to prefix
substuents
1. alphabetical order
2. number carbon its on
What is the general formula for an alkane?
CnH2n+2
What happens to boiling points in alkanes? Are they soluble in water? What is the
general density? (will it float or sink in water?)
Get higher as molecular weight increases; decreases with branching
They are not soluble in water
Plain alkanes less dense
Haloalkanes are more dense
What is the general formula for a combustion reaction?
CnH2n+2 + O2 H2O + CO2
What is the general formula for a monohalogenation reaction?
CnH2n+2 + X2  CnH2n+1X + HX
What is the general formula for a dihalogenation reaction?
CnH2n+2 + 2X2  CnH2nX2 + 2HX
Alkenes
What is an alkene?
Unsaturated carbon chain, contains at least 1 double bond
How do you name alkenes?
1 Count longest chain
2 Name double bond with lowest number
3 Name substituents.
What is the general formula for an alkene?
CnH2n
What are cis/trans structural isomers? How do you determine whether a molecule
is cis or trans?
Cis/trans isomers have different rotations about their double bonds. Cis=biggest
chains on same side; trans=biggest chains on opposite sides
What does the hydrogenation addition reaction to an alkene look like?
CnH2n + H2  CnH2n+2
Basically, alkene to alkane
What does the halogenation addition reaction of an alkene look like?
CnH2n + X2  CnH2nX2
Alkene to dihalogenated alkane
What does the hydrohalogenation of an alkene look like?
CnH2n + HX  CnH2n+1X
Explain Markovnikof’s rule in your own words.
The atoms with the least hydrogens on the double bond gets the halogen.
The atoms with the most H’s gets the H.
What does the hydration addition reaction of an alkene look like?
CnH2n + H2O  CnH2n+2O
Alcohols and ethers
What is an alcohol?
A carbon chain with an OH group attached.
How do you name alcohols?
The OH group takes priority. OH group gets lowest number along chain. Follow
other rules after that.
What is the general formula of alcohols?
CnH2n+1O
What does the dehydration of an alcohol look like?
CnH2n+10  CnH2n + H2O
What does the dehydration of two alcohols together look like?
Remove water and form ether CH3OH + CH3OHCH3OCH3 + H2O
Explain hydrogen bonding.
FON are very electronegative. Can bond to carbon intra and intermolecularly
Which has a higher boiling point, alcohols or ethers? Why?
Alcohols, hydrogen bonding
How do you name an ether?
Name substituent groups and add ether.