optical rotation of zero and equal mixture of two enantiomers
If all of the chiral centers are of opposite R/S configuration between two stereoisomers, they are _______.
If at least one, but not all of the chiral centers are opposite between two stereoisomers, they are _______.
A substance that is a single, pure enantiomer (i.e., has 100% ee) is called homochiral or optically pure.
A ________ is a non-optically active member of a set of stereoisomers, at least two of which are optically active. This means that despite containing two or more stereogenic centers, the molecule is not chiral. It is "superposable" on its mirror image.
meso compound or meso isomer
In stereochemistry, an _____ is one of a pair of stereoisomers. The two isomers differ in configuration at only one stereogenic center.
anomer differ at the anomeric carbon
If one enantiomer has a melting point of 80 the other will have _____
If one enantiomer has optical rotation of +45 degrees the other has ____
80 (same physical properties)
The process of separating two enantiomers is ______
Enantiomer A has an absolute configuration of R and optical rotation of +87, what is enantiomer B's absolute configuration and optical rotation?
S and -87
A mixture of two racemic compounds will give a mixture of _____ stereoisomers?
Longer carbon chain means ______ hydrophobic
Higher retention factor means
it elutes first (non polar) in thin layer chromatography
polar interact with silica gel
High performance chromatography
But in reverse HPC polar elute first
Ester: 1735 (which could be part of carboxylic acid since ketones are around 1700)
Alcohol/OH: 3100-3300 (broad) alcohol typically 3350
- Ketone: 1750
- Alkene: 1650
- NH: Sharp 3300
- Carboxylic acid: 3000
- Aldehyde C-H: 2700-2800
HNMR n + 1 rule
A signal will be neighboring carbon hydrogens plus 1.
ex. doublet has one adjacent hydrogen + 1 to make doublet.
Whats the degrees of unsaturation formula and what two things count as degree of unsaturation?
2C + 2 + N - H - X / 2
ring and double bond
SN2 reactions operate by
____ order kinetics
1°>2°>3° reactivity sequence
complete inversion of stereochemistry
does it have rearrangement?
complete absence of rearrangement
SN1 or SN2
____ depends on substrate concentration only (rate of leaving group loss.?
Depends on substrate concentration and concentration of nucleophile cuz it's one step_____
Both SN1 and SN2 depend of solvent and temperature.
SN1 depends on substrate concentration (rate of leaving group loss)
SN2 cuz it's one step
SN2 reactions proceed ______ with increased steric hindrance/ substituent size.
SN1 reactions proceed ____ with increased steric hinderance/ substituent size.
faster cuz SN1 prefer more stable carbocation tertiary > secondary >> primary
alcohol --------> ester
-----> is ______
what compound has IR spectrum of 1735cm -1
ester = 1735 cm-1
strongest acid is one with strongest electron withdrawing group closest to molecule.
Cl > OH
LiAlH4 reduces acids (carboxylic acids) to _____
alcohol + carboxylic acid =
only primary alcohols can be oxidized to carboxylic acids
proton between two carbonyl groups is highly acidic
The pI (isoelectric point) for enantiomers is _____
same physical properties for enantiomers
How to determine how many stereoisomers carbohydrates have, what formula?
n - number of chiral centers
Positive test for benedicts test would need a reducing sugar that had a ketone or aldehyde at first or last carbon to reduce copper and be oxidized in process.
If both ends have carboxylic groups it won't work
Meso compounds (achiral) must have how many chiral centers.
any even number greater than or equal to 2.
Base - Adenine, Guanine, Cytosine, Thymine
Nucleosides: adenosine, guanosine, thymidine, cytidine
Nucleotides: Base + ribose + phosphate
- adenosine tri phosphate
- guanosine tri phosphate
- cytidine tri phosphate
- thymidine tri phosphate
n - any number usually from 3-9
EX- C3H6O3 - triose
C9H18O9 - Nonose
Cholesterol plasma membrane buffer
At low temperatures, cholesterol _____ membrane fluidity
by preventing membrane lipids from packing close together.
At high temperatures, cholesterol ______ membrane fluidity.
how to look at aldol in your head:
the alpha proton becomes a double bond and you wipe off the ketone from the other molecule and attach there
reactants - pka 25
products - pka 35
which is favored?
products - weaker acid (high pka)
John HIO biochemistry
Hydrazone, Imine, Oxime, similar structure (NH2/NHR, R/H, OH)
Na2Cr2O7 / H2SO4, H2O (Jones) can oxidize _______ and _______
Tollens reagent can only oxidize _______
alcohols and aldehydes
primary amine + ketone = _______
_________ 4n + 2 pi bonds
for aromaticity, n can be any integer
Steric number is ______
sigma bond + lone pair
Beyonce at the VMF
what this mean?
Boiling point inverse to Vapor pressure, Melting point, and Freezing point
Inductive effects on carboxylic acid derivatives making them more reactive is more electronegative atoms closer to carbonyl to give carbonyl a partial positive (EW)
Resonance stability (ED) to make things less reactive is having a resonance and no other competing resonance and also the carbonyl carbon and ED atom in same period.
ex- amide less reactive than carboxylic acid with OH because N is less electronegative than O and will be more willing to donate as oppose to withdraw it's electrons for resonance stability and N in same period as C also so good p orbital overlap.
coenzyme (non protein organic cofactor) binds apoenzyme (inactive) = ________
0 order units K _____
1st order ____
2nd order ____
3rd order _____
0 = M/s
1 = s-1
2 = s-1 * M-1
3 = s-1 * M-2
intermediate vs catalyst
reactant then on product side in next step ____
product side then reactant side in next step ____
Spontaneous or Non-Spontaneous and push reaction to right/products or left/reactants ?
K > Q
Q > K
K = Q
K > 1
K < 1
K = 1
K > Q = Spontaneous -ΔG/ push to products/right
Q > K = Non-spontaneous +ΔG/ push to left/reactants
K = Q = ΔG = 0
K > 1 = spontaneous / -ΔG / push to right/products
K < 1 = non-spontaneous / +ΔG / push to reactants/left
K = 1 = ΔG = 0
What's the 0th law of thermodynamics?
What's the 1st law of thermodynamics?
2nd law thermo?
expansion - work done by gas (-w)
compression - work done on gas (+w)
0th law: If obj 1 in thermodynamic equilibrium with 2, and 2 is in thermoequilibrium with 3 then 1 is with 3, allow for universal temp scale
1st law: Energy can't be created or destroyed only converted from one form to another. ΔU = Q + W
- ΔU = Change in internal energy OF GAS
- Q = Heat (-Q heat release/ +Q heat added)
- W = Work (-W work done by gas/ +W work done on gas)
- adiabatic ΔU = 0
- isothermal Q = 0
- isovolumetric / isochoric W = 0
Heat flow from hot to cold and will never be seen flowing from cold to hot spontaneously
CxHy + O2 ---> ____CO2 + ____H2O
C5H12 ----> _____ + ______
CxHy + O2 ---> xCO2 + y/2 H2O
C5H12 ----> 5 mol CO2 + 6 mol H2O
more stable trans both substituents equatorial (sideway not down which is axial)
more stable cis bulkier substituent equatorial
A catalyst that has a different phase (s, l, g) than the reactants it catalyzes is called _____
homo would be same phase like gas to gas or liquid to liquid
H2O + H2O = H3O+ is an example of _____
autoionization - same substances react to form ion.
constant velocity = acceleration is zero
Newton 1st law ______
Newton 2nd law ______
Newton 3rd law ______
Newton 1st law- object keeps moving unless a force stops it from moving
Newton 2nd law - F = ma (kg * m/s^2)
Newton 3rd law - When a force is applied there's an equal reaction of force in opposite direction opposing that force that's equal like for example with pushing a desk
object keeps moving unless a force stops it from moving ______
Newton 1st law-
F = ma (kg * m/s^2)
what is this?
Newton 2nd law -
When a force is applied there's an equal reaction of force in opposite direction opposing that force that's equal like for example with pushing a desk
Newton 3rd law -
_____ pressure is transmitted undiminished to every portion of the fluid and to walls of the container
P = F/A
F1D1 = F2D2
Small force applied to small area over large distance provides a large force to a large area over a small distance
SG of 0.2 means 20% object submerged in water
SG = weight of fluid displaced
SG > 1 MEANS _____
Volume flow rate = ΔP*pi*R^4 / 8NL
L= length of tube
increase ΔP = increase volume flow rate
increase length of tube and viscosity = decrease volume flow rate
_____ water molecules attracted to each other
____ water molecules attracted to something else (like tube so meniscus)
* water level higher where fluid travels faster
formula for temp in C
formula for temp in F
Tc = Tf-32 (5/9)
Tf = Tc(9/5) + 32
Which has more pressure and less volume, real gas or ideal gas?
Ideal has operates under ____ temp and ___ pressure
ideal gas more pressure and less volume than real gas
(volume occupied by gas molecules negligible in ideal gas, collisions are elastic no KE lost, all KE related to pressure, gas molecules don't touch except during collision)
ideal gas - high temp / low pressure
electrostatic force = kq1q2/r^2
electric field = kQ/r^2
electric potential = kQ/r
resistivity = replay for formula
whats the formula?
what does increasing length do to resistance?
R = p(L/A)
p = resistivity which if it increases increases resistance
copper gold silver are conductors with little resistance cuz they metals
non metals are insulators- more resistance
increasing length increases resistance cuz current would have to travel farther
increasing area decreases resistance cuz there's a bigger area to flow through
volmeter need huge resistance (ideally infinity) since hooked up in parallel and u want as much current to flow thru resistor and voltmeter in series would block current
ammeter hooked up in ____ because it has ___ resistance
ammeter hooked up in series little resistance.
ideal ammeter has zero resistance
Does increasing charge increase capacitance?
increase capacitance by making pieces of metal _____
place piece of metal closer or further apart increase capacitance?
No, increasing charge does not increase capacitance because voltage would increase and ratio would be same C = Q/V
dielectric k is 1 for air and vaccum and anything else is larger
two formulas for energy stored in a capacitor
HINT: If you use C you can see (c) the V^2
E = 1/2CV^2
E = 1/2QV
with dielectric how you increase capacitance
with battery - increase charge
w/o battery decrease voltage
C = Q/V
right hand rule proton
left hand rule electron
middle finger -
- thumb - force
- pointer - qv - velocity and charge or current
- middle finger -magnetic field
magnetic force = qvB
less substituents = _____ heat of hydrogenation
substituents equal more steric hinderance = ______ heat of hydrogenation
similar changes in heat of hydrogenation and heat of combustion
higher heat of hydrogenation
higher eat of hydrogenation (cis > trans heat of hydrogenation if substituents equal)
______ enhance the RNA pol and promoter interaction during transcription
_____ located on the DNA chromosome; activators bind here and loop DNA to bring specific promoter to initiation complex to enhance transcription of genes. activator interacts with mediator complex to recruit RNA pol and general TFs.
TFs transcription factors bind to ____
_____ bind to silencers located on DNA strand
proto-oncogene vs oncogene
which one cancer which one normal
proto-oncogene - normal
oncogene - cancer
______ mutation new AA same type as original (Arg -> His both basic)
_____ mutation new AA different type (Arg -> Asp, basic to acidic)
____ A -> G purine to purine
____ A --> T purine to pyrimidine
____ gene on one chromosome swapped for gene on another
___ gene one same chromosome swapped
sanger sequencing - set the base pairs for coding region starting from bottom + to top - (5` to 3`)
Type ______ enzymes target modified (e.g. methylated, hydroxymethylated) DNA.
Type _____ enzymes cleave within or at short specific distances from their recognition sites and often require magnesium (Mg2+)
Type _____ enzymes cleave at sites a short distance from their recognition sites and require ATP (but do not hydrolyze it). S-adenosyl-L-methionine stimulates this reaction, but is not required.
Type ______ enzymes cleave at sites remote from the recognition site; they require both ATP and S-adenosyl-L-methionine to function.
_____ used to simultaneously analyze the gene expression profiles of 1000s of genes to study disease
______ - used to assay location of specific DNA sequence
Florescence in situ hybrid
which is more muscular/thick, atria or ventricles?
which is more muscular/thick/elastic, veins or arteries?
- stimulates bile production by liver
- secreted by s. intestine/duodenum
- stimulates pancreas to release H2O and HCO3- to neutralize HCl
- Inhibits gastrin to inhibit HCl release