Chem-Phys Flashcards
What is a stereospecific reaction
a reaction in which the stereochemistry of the reactant completely determines the stereochemistry of the product, without any other options
What is the thin lens formula
1/o + 1/i = 1/f
electromagnetic radiation is directly proportional to….
the number of photons emitted
Tera (T) SI unit prefix
10^12
Mega SI unit prefix
10^6
Giga SI unit prefix
10^9
Joules units
( kg * m^ 2 )/ s^s
what type of bond is Disulfide bonds
a covalent bond, between two sulfur atoms (–S–S–) formed by the coupling of two thiol (–SH) groups on Cysteine AA.
What amino acids are acidic? what is their net charge at physiological pH?
Aspartic acid (Asp, D) and glutamic acid (Glu, E) are the acidic AAs, will have neg negative charge at pH 7.4, Require decrease in pH to become neutral
separation by isoelectric point
protein will stop when it becomes neutral (pI)
What are the 4 assumptions made of “ideal gas”?
1) The gas particles have negligible volume.
2) IMF is negligible
3) The gas particles move randomly in agreement with Newton’s Laws of Motion.
4) Gas particles have perfect collisions with no lost energy
What is the ideal gas law?
PV=nRT
What is the function of rhodopsin?
allow for detection in low light conditions
Is a compound composed of mostly hydrogen and carbon hydrophobic or hydrophilic?
hydrophobic. Hydrophilic compounds are polar, charged side chains
What are the four charged amino acids?
(street) KRED- lysine, arginine, glutamate, aspartate
What are 2 types of linkages in glycogen structure?
alpha-1,4-glycosidic bond with branches joined by alpha-1,6-glycosidic bond.
What is UDP-glucose’s role in glycogen synthesis?
UDP glucose added to nonreducing end of glycogen molecule with release of UDP
What does a phosphatase enzyme do?
removes a phosphate group from a protein
In beta - decay, does the element go up or down on periodic table?
Electron emitted, neutron converted to proton and up 1 in periodic table
How will the rate of a catalyzed reaction be affected if the solid catalyst is finely ground before it is added to the reaction mixture?
The rate will be faster because a greater surface area of catalyst will be exposed.
Ohm’s law
V (volt)=I(Amperes) * R(ohm)
Electrical field equation and SI units
E= Fe/q = kQ/ r^2 (N/C or V/m)
What angle is considered half a wavelength, 180 degrees or 90 degrees?
180 degrees. Waves at 180 degrees of each other will produce destructive interference
What is the geometry of CH4?
tetrahedral, carbon bonded to 4 hydrogens with no lone pairs
What types of elements act as electron acceptors?
those with high electron affinity
Doppler effect equation
f’= (v +/- Vd)/ (v -/+ Vs). top sign forward, bottom sign away
doppler equation for frequency
Δf/f = -v/c
what travels faster– light or sound?
light
equation for buoyant force
Fb=-p g V. v = volume of displaced fluid. buoyant force opposes Fg= mg
how does the number of incident photons change at electrodes
only changes number of electrons released (proportionally) NOT energy
what does electron energy depend on
photon energy, work function, and potential difference
how does a charged particle move in an electric field?
a charged particle accelerates in an electric field
empirical formula
relative number of atoms each compound contains
how do you calculate the number of stereoisomers in a molecule
2^ n, where n is the number of chiral molecules in the compound
electric field lines move from what point to what point
postive to negative
rank in increasing size Sodium ion, Potassium ions, Chloride ion
Na+ < Cl - < K+
what are the charged amino acids
KRED- lys (+), arg (+), glutamate (-), aspartate (-)
what are the minimal variables needed for ultrasound via Doppler effect
speed of sound, frequency of sound waves emitted and observed.
Will liquids with a high vapor pressure evaporate more easily or less easily?
More easily, have weaker IMF (likely less H-bonding)
What is vapor pressure?
Vapor pressure is a measure of the pressure exerted by a gas above a liquid in a sealed container. Strong IMF in a liquid mean less evaporation and lower vapor pressure. Weaker IMF mean more evaporation and higher vapor pressure
What is principal quantum number?
describes the energy of an electron and the most probable distance of the electron from the nucleus
Describe basic structure of a fatty acid
a straight chain hydrocarbon tail and carboxylic acid group
If ligands are hydrophobic with anionic or electronegative features, what type of amino acids will be in active site?
hydrophobic and positively charged amino acids (hydrophobic- gly,val,ala,leu,ile and pos aa- arg, lys)
what is chirality
a figure that is not identical to its mirror image.
what is sublimation?
solid –> gas, can be used as separation technique of 1 subliminal material and 1 non subliminal material
ratio of the density of an object to the density of the fluid it is submersed in is equal to
ratio of the weight of the object in air to the difference of submersed weight and weight in air.
at pH 7, acidic groups on molecules will have what charge?
-1
What is the equation for energy of a photon?
E=hf (units– eV= 1.6*10^-19C)
What is the function of a protease?
Cleave peptide bonds
nano
10^−9
micro (µ)
10^-6
what is more polar 2-butanone or n-butanol?
butanol is more polar due to its ability to h-bond
When sitting up, why do you lean forward
to keep center of gravity in equilibrium, or else torque would make you fly back
What charge does a phosphate group have?
-1
What is a coordinate covalent bond?
Two electrons in the bond are donated by a single atom, as opposed to equal donation in traditional covalent bonding. Atom needs one lone pair. Examples)NH4, H3O
What type of bond is formed in Lewis acid–base interaction between a metal cation and an electron pair donor?
Coordinate covalent bond
What does the coordinate number refer to?
The number of ligands attached to the molecule
what is log .1
-1