NS2: CPF Flashcards
partial pressure
For a gas that is a component in a mixture of gases, partial pressure is defined as the pressure that this gas would exert if it took up the same volume by itself.
Dalton’s law states that the total pressure of a mixture of gases is equal to the sum of the partial pressures of its components.
Pgas = XgasPtotal
where Pgas is the partial pressure and Xgas is the mole fraction of a gas but Xgas = ngas/ntotal if more information is needed
Raoult’s Law
the presence of solute in a mixture decreases its vapor pressure
P = XAPA°
where P is the vapor pressure of the solution, XA is the mole fraction of the solvent, and PA° is the vapor pressure of the pure solvent
Explains why adding solute makes things harder to boil; water molecules have a harder time breaking through to the surface in the presence of more solute
Conservation of Energy
states that energy can neither be created nor destroyed, just transferred from one form to another.
KEinitial + PEinitial = KEfinal + PEfinal
If we need to account for nonconservative forces such as friction, we can do so using the equation Etotal – Enonconservative = Efinal
E = PE + KE
Hemoglobin
- function
- composition
- graph
metalloprotein that plays an essential role in gax exchange in humans, transporting oxygen to the body tissues and carbon dioxide to the lungs for exhalation. They are found in erythrocytes and consists of four globular protein subunits, forming a quaternary structure; each subunit contains one heme group that contains one iron cation capable of binding oxygen in the Fe2+ state.
- With four subunits containing one heme each, each hemoglobin can carry up to four oxygen atoms
- Binding of oxygen to ANY OF THE FOUR binding sites causes an increase in oxygen affinity of the remaining sites → aka COOPERATIVITY
Cooperative binding can be recognized by its signature sigmoidal or S-shaped curve → for hemoglobin-oxygen binding, the y axis is usually the percent saturation of oxygen, while the x axis is the partial pressure of oxygen
The Bohr Effect
dictates why oxygen is dropped off at the tissues despite the supposedly high affinity it has to the hemoglobin.
The higher the partial pressure of oxygen, the higher the oxygen saturation tends to be
Under certain conditions (ie low plasma pH and increased levels of CO2), this binding curve can shift toward the right along the x-axis and decrease the hemoglobin-oxygen affinity, allowing oxygen to be more easily dropped off in the tissues
States of matter
Solids: fixed shape; fixed volume, thus are incompressible; no flow, but particles do vibrate in place
Liquids: fixed volume; no fixed shape, thus can flow to assume the shape of their container; has viscosity (resistance of movement)
Gas: no fixed volume or shape, thus able to be compressed (meaning density of a given gas is not constant and varies based on its container)
Phase Changes
- 6 types
- exo or endo?
Endothermic: require input of heat bc breaks bonds or intermolecular interactions
- Melting / fusion = solid → liquid
- Evaporation = liquid → gas
- Sublimation = solid → gas
Exothermic: release heat bc of bond formation or increase in IMF strength
- Condensation = gas → liquid
- Freezing = liquid → solid
- Deposition = gas → solid
Define the following:
- solubility
- saturated soln
- supersaturated soln
Solubility: degree to which a solute (particles) dissolves in a solvent (fluid substance); solubility of ionic substances in water increases with temperature, while the opposite pattern is observed for gases (bc higher temperatures provide gases w more kinetic energy that they can use to escape the soln)
– Like dissolves like
Saturated soln: when the maximum amount of solute that can be dissolved has been added
Supersaturated soln: heating of a saturated soln in order to dissolve more solute, then cooling it
PV = nRT explained
Pressure of a gas given as Pascals (Pa), atmospheres (atm), mmHg, or torr → 1 atm = 760 mmHg = 760 Torr = 105 Pa (N / m2)
Volume: 1L = 103 mL = 103 cm3
Mole: given as 6 x 1023 atoms / molecules of a substance
R: universal gas constant
Temperature: provides info of avg KE of the molecules in a gaseous sample, where T ~ KEavg = ½ mv2
- T may be given in degrees Celsius or Kelvin → Tk = Tc + 273
- Absolute zero (0 K) is the lowest temperature that any substance can exist, and at this temperature, the molecules in a gaseous sample will have no energy and will be motionless
titration
process of finding the concentration of an unknown solution (analyte) by reacting it w a soln of known concentration (titrant)
Flat regions of titration curves represent buffering solutions (roughly equal mix of an acid/base and its conjugate base)
At equivalence points during the titration (steep, near-vertical sections of the curve), the number of acid or base groups added to the soln is equivalent to the number of base / acid groups in the original unknown soln → NaVa = NbVb, where N and V are the normality (mol/L) and volume of the acidic and basic solutions, respectively
Titrant is added to the analyte until the endpoint, either by reaching a certain pH value (acid-base reactions) or when a precipitate appears (precipitation reactions)
– For acid-base reactions, an indicator generally undergoes a color change near the desired pH → eg. phenolphthalein changes color above a pH of 7 when a strong base is being titrated by a weak acid
Functional Groups, set 1
- Alkanes
- Alkenes
- Alcohols
- Aldehydes
- Ketones
- Carboxylic Acids
Alkanes: hydrocarbon w only single C-C bonds
Alkenes: hydrocarbon w at least one C=C double bond
Alcohols: RC–OH
Aldehydes: RC(=O)H)
Ketones: RC(=O)R’
Carboxylic acids: R(C=O)OH
Functional Groups, set 2
- Amides
- Esters
- Acid Anhydrides
- Acid Halides
- Amines
- Imines
- Enamines
Amides: R(C=O)NR’R’’ Esters: R(C=O)OR’ Acid anhydrides: R(C=O)O(C=O)R’ Acid halides: R(C=O)X Amines: R–NH2, R–NHR’, or R-NR’R” Imines: R=NH or R=NR’ Enamines: C=C–NH2, C=C–NHR, or C=C–NRR’
Functional Groups, set 3
https://quizlet.com/140558809/mcat-functional-groups-and-symbols-flash-cards/
YOU SHALL NOT PASS WITHOUT DOING ALL OF THESE; mark as “1” until you get all of them
Percent Dissociation
eg. Given 2 moles of HF in 0.1 L of water, provide % diss.
percent of original acid concentration that has divided into ions
Original [HF] = 2 moles / 0.100 L = 20 M
[H+]/[HF] = (10-4 M H+) / (20 M HF) = 5 x 10-6
% dissociation = 5 x 10-6 x 100% = 5 x 10-4
THUS,
% dissociation = 5 x 10-4% = 0.0005%
Isomers; two types
molecules w the same number of atoms but different connectivity or spatial arrangement
Structural isomers: diff connectivity
- Chain isomers: diff arrangements of the carbon backbone
- Functional Isomers: molecular formula is the same but different functional group
- Positional isomers: same functional group but different location
Stereoisomers: different spatial arrangement
- Cis-trans: most common isomerism involving alkenes bc rotation about pi bond is restricted, thus substituents are given priorities
- —- Cis / Z isomer: highest priority groups for each carbon are on the same side of the molecule
- —-Trans / E isomer: opposite sides
Optical isomers
come in pairs and typically contain one or more chiral centers
Enantiomers: non-superimposable mirror images w similar chemical and physical properties but polarize light in opposite directions → eg. your hands
Diastereomers: multiple chiral centers but isomers only differ at some; similar chemical but less similar physical properties
Chiral Carbon labelling:
Lowest priority pointed away form observer; rest will be numbered 1 → 3 in a decreasing priority order (ie highest priority is numbered first)
If counterclockwise, then S chiral center
If clockwise, then R chiral center
Work
Work is measured in joules and the work-energy theorem tells us that Wnet = ΔKE.
Power
Power is defined as work divided by time (P = W/t). Its units are watts (W), and 1 W = 1 J/s.
Rearranging the units of J/s indicates that power can also be expressed as a constant force multiplied by a constant velocity (P = Fv).
Electromagnetic waves
transverse waves that can propagate through vacuum, as well as through other media such as air and water; have both electrical and magnetic components, with amplitudes perpendicular to each other and to the direction in which the wave is propagating
EM waves propagate through space at the speed of light (c = 3 × 108 m/s)
EM Wave Equations (2)
The standard unit for all EM radiation is the magnitude of the wavelength (nm), which is measured btwn two successive peaks
The corresponding frequency of the wave is the number of complete wavelengths that pass a given point per second. Frequency is usually measured in hertz (Hz).
v = λf
Thus, longer wavelengths correspond to lower-frequency radiation, and shorter wavelengths correspond to higher-frequency radiation.
E = hf = hc/λ)
where h is the Planck’s constant
– An increase in frequency produces a proportional decrease in wavelength, with a corresponding increase in the energy of the photons that compose the light.
– Upon entering a new medium, the velocity and wavelength of light change while the frequency remains unchanged.
Define the following:
- isotype
- half-life
Isotope: varieties of an element that differ by the number of neutrons in its nucleus; share the same atomic number and chemical properties → often used in radiolabeling techniques
Half-life (t1/2): time required for half of the parent isotope of the sample to decay into daughter (radiogenic) isotopes → 100% to 50% (1 half life) to 25% (2) to 12.5% (3) to 6.25% (4) to 3.125% (5) to 1.0625% (6)
extractions
technique used to separate two or more compounds in solution by manipulating their solubility properties using acid-base chemistry
Setup usually has a layer of less-dense organic solvent on top of a layer of water, which is a highly polar compound → non polar compounds will move to organic layer, while polar / charged ones will remain in the aqueous layer
Mono- /Poly- atomic ion nomenclature
- u should alrdy kno oxyanion nomenclature
Monatomic ions use the suffix -ide, as in hydride (H−) or oxide (O2−)
Polyatomic Ion nomenclature:
The ion with the lesser charge will use the suffix “-ous,” and the ion with the greater charge will use the suffix “-ic.”
– Eg. iron (II) cation, Fe2+, is termed the ferrous ion, while the iron (III) cation, Fe3+, is the ferric ion
If the polyatomic anion includes a hydrogen (H+) ion, “hydrogen” or the prefix “bi-” is added to the name of the parent anion.
– Eg. CO32− ion is carbonate, so HCO3− can be termed hydrogen carbonate or bicarbonate
“dihydrogen” denotes the presence of two H+ ions
– Eg. H2PO4− can be called dihydrogen phosphate
