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Question 1

Infrared Spec

Alcohols
Acids
Ketones
Amines

Answer 1

measure molec vibrations: stretching, bending and rotations
Best to identify functional group
Alcohols - broad peak 3100-3500
Acids - broadest - C=0 and O-H 
Ketones - sharp
Amines- sharp

Question 2

Why does O-H group have broad peak in IR

Answer 2

The variable pull on H changes the apparent mass of H atom - this is stretching.

Question 3

How to determine how many signals in C-NMR?

Answer 3

number of different Cs in the compound. Different means different things attached to it. Eg benzoic acid has 5

Question 4

torisional strain

Answer 4

occurs between atoms on same compound. Caused by repulsion between electrons/bonds when atoms are close

Question 5

staggered vs eclipsed

Answer 5

staggered, groups on adjacent C as far apart as possible.

eclipsed - as close as possible

Question 6

gauche

Answer 6

staggered but eg 2 methane groups are close (like at 12 and 2)

Question 7

anti

Answer 7

staggered, like mthane groups at 12 and 6

Question 8

SN1

Answer 8

Rate can never be more than rate determining step
LG leaves, making carbocation
nuc attacks
rate only depends on the conc or original mcule bc it’s the only reactant
Best in polar and protic solvents eg water and alcohol
Will usually give a racemic mixture because of the planar carbocation!

Question 9

SN2

Answer 9

nuc attacks and Lg leaves
ONLY 1 step
depends on conc of both
strong nuc attack from back
polar aprotic solvents 
Why not protic? Because H would bond to nuc and stop it from attacking, remember we need the nuc to be really strong in sn2 bc it has to force the lg to leave

Question 10

When will Sn1 happen over sn2?

Answer 10

Tertiary>2>1>methyl
planar
achiral

Question 11

SN2 over SN1?

Answer 11

methyl>1>2>3
chiral transition state
rxn flips the bonds

Question 12

Great LG

Answer 12

weak bases, halogens

Question 13

Strong nucs

Answer 13

strong bases, larger is better

RO->HO->RCO2->ROH>H2O

Question 14

Elimination rnx

Answer 14

alkane - alkene via removal of halide or OH

Question 15

E1
How many steps
rate determining step
mech
favorable conditions

Answer 15

Unimolecular elim.
2 steps carbocation intermediate like sn1
only conc of substrate matters
LG leaves eg Cl
weak nuc (OH-) pulls H off of other C, makes alkene
polar, highly sub C groups, weak nuc

Question 16

E2

Answer 16

bimolec elim
1 step like sn2
conc of substrate and base (strong nuc!)
Strong nuc plucks off H, halide (LG leaves too)
NB! Goes after more substituted C so that double bond is somewhere in the middle of the cpound instead

Question 17

enantiomer

Answer 17

isomers that are mirror images

Question 18

structural isomer

Answer 18

same molec formula

Question 19

geometric isomer

Answer 19

same atoms, bonds, different spatial arrangement

Question 20

ortho, meta, para

Answer 20

ortho - adjacent 1,2 position
meta - 1,3 poisition
para - 1.4

THINK PARa = even out

Question 21

solubility inc or dec with Temp?

Answer 21

dec

think heating mixes things up

Question 22

IR spec - what does a high peak mean?

Answer 22

it means there is more of that particular group relative to others in the sample
but it’s not quantifiable, like don’t use IR to figure out concentrations of a group in a sample

Question 23

what is the best way to decipher an unknown in large quantities?

Answer 23

extraction

Question 24

identify unknowns on small scale?

Answer 24

you can use gas chromatography
paper chrom
mass spec

Question 25

single bond

bond type
hybridization

Answer 25

sigma

sp3

Question 26

double bond

bond type
hybridization

Answer 26

sigma and pi

sp2

Question 27

triple bond

bond type and hybridization

Answer 27

1 sigma, 2 pi

sp

Question 28

what has a higher bp?

cis alkene or trans?

Answer 28

cis because of the dipole moment that is created

Question 29

what has a higher melting point?

cis or trans alkene?

Answer 29

trans, more effective arrangement

Question 30

what is a chiral mcule?

Answer 30

a mcule that is not superimposable on its mirror image

Question 31

what is a meso mcule?

Answer 31

a mcule that has chiral centers but is achiral meaning the mirror images can superimpose

conversely, you can have a mcule with no chiral centers and still have be chiral (cannot superimpose) just because of geometry in space

Question 32

what does amphipathic mean?

vs amphoteric

Answer 32

mcule has both polar and nonpolar regions

amphoteric can be an acid or base

Question 33

what does alpha decay emit?

Answer 33

2 protons and 2 neutrons

Question 34

how many neutrons do beta and gamma radiation emit?

Answer 34

none!