Alkanes Flashcards
At room temperature, formulas CH4 to C4H10 are
Gases
At room temperature, formulas C5H12 to C16H34 are
Liquids
What is the general formula for alkanes?
CnH2n+2
Straight-chain isomers have
Higher bps and mps
Why do branched isomers have lower bps and mps?
They reduce SA, which decreases to weak IMFs
Nucleophiles are attracted to
Positive charges
What are nucleophiles?
Electron-rich species that are often negatively charged
Nucleophiles correlate with
Basicity
The stronger the base the
Stronger the nucleophile
Bases act as
Electron donors
Stronger nucleophiles are ones that have
More of a negative charge / strong base
In protic solvents, which are the better nucleophiles?
Larger ions
In aprotic solvents, nucleophilics are related to
Basicity
The best leaving groups are
Weaker bases
SN1 is
Unimolecular nucleophilic substitution
SN1 is associated with the formation of
Carbocation
How many steps are in SN1?
Two
What are the two steps of SN1?
- Dissociation of substrate molecule into carbocation and leaving group
- Combination of carbocation with nucleophiles to form substituted product
SN1 depends on the
Stability of carbocations
Which solvents are ideal for SN1?
Polar protic
SN1 reactions do not require
Strong nucleophiles
SN1 reactions produce
Racemic mixtures
SN2 is
Bimolecular nucleophilic substitution
How many steps are in SN2?
One