Section 1
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chemical formula
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Cards (252)
Section 1
(50 cards)
chemical formula
-how many of each element in a molecule, like NH3 tells us we have 1 N and 3 H
metalloids
have characteristics of both metals/nonmetals (boron, silicon, arsenic, germanium) -not aluminum or po
ionic bonds
-2 oppositely charged ions attract each other -ion- when gain/lose electrons -lose electron then positive charge, gain electron then negative charge -cation- positive charge -anion- negative charge -electrons not shared -once ions form then electrostatic attraction between them, result in ionic bond
transition metals
-element whose atom has an incomplete d subshell or which can give rise to cations with an incomplete d subshell -iron- [Ar] 4s^23d^6 or 3d^6 4s^2 -incomplete d subshell -Zn not one since full d shell when cation and when an atom -groups 3-12
compound
elements held together through chemical bonds -stability of chemical bonds because of electrostatic attractions
groups
vertical columns on periodic table -labeled 1-18 or 1A 2A 3A (skipping d subshell) to 8A when thinking about valence electrons -don't label f block -elements in groups have same number electrons so similar characteristics
atomic radius
-AKA atomic size -electrons not in orbit around the nucleus so can't find radius using equation of a circle -Van der waals radius- measure how close can put two atoms of same type together without combining, half of that is radius (atomic radius) -measure length of covalent bond and divide by 2 -as go to right, radius gets smaller because protons pull on electrons more -as go down group add more shells, larger atomic radius (electron shielding) -can explain using Coulomb's Law -electron shielding- when electrons in inner shells "shield" or repel other electrons from the nucleus -ionic radius-anion bigger than neutral atom since have another electron, cation smaller because lost one electron
different isotopes of hydrogen
-protium- hydrogen with 0 neutron -deuterium- hydrogen with 1 neutron -tritium- 2 neutrons
counting valence electrons from main groups
-valence electrons- electrons in outermost shell/energy level -look at number of electrons in last energy level of electron configuration
metals
-solid at room temperature except mercury -malleable, ductile (can make them into wires) -good conductors of heat/electricity -left side of table -shiny, dense, except Hg all are solid, can bend/shape them (malleabile), conduct electricity well -bound metals very willing to share electrons, so freely bound electrons can move from metal atom to metal atom to create a sea of electrons, making the compound malleable and allowing to transport electricity -those with low electronegativity more metallic in nature (more likely to share electrons) -s,d,f and part of p block considered metals
space-filling model
-gives sense of size and shape of atoms in compound
2 clouds no lone pairs
linear (180 degrees)
-can elements have an infinite number of neutrons?
-as number of isotopes increase/decrease, atom becomes less stable until finally element decays faster than elements can be gained
formula unit
-largely do not exist in nature -ionic compounds
alkaline earth metals
-reactive (not as much as 1) so never found in pure state in nature -only need lose 2 electrons
first/second ionization energy
-first ionization energy is the energy needed to remove the most outer valence electron of an atom -second ionization energy is the energy needed to remove the 2nd most outer valence electron of an atom -higher than first because higher effective nuclear charge, less shielding, -you will see a large jump in ionization energy when moving up principle energy levels since there will be less electron shielding
relative abundance
Relative abundance of an isotope is the fraction of a single element that exists on Earth with a specific atomic mass.
halogens
-group 17 -very reactive nonmetals, colorful, corrosive, salt former, diatomic
nonmetals
-brittle in solid form -not malleable, poor conductors of heat/electricity -right side of table
molecule
-groups of atoms held together by only covalent bonds -ionic compounds do not equal molecules
covalent bonds
-2 atoms share electrons -stability of bond from shared electrostatic attraction between 2 positively charged nuclei and shared negatively charged electrons = molecule
atomic weight and atomic mass
-atomic mass measured in amu, measure one atom -defined using carbon 12 has 12 amu -atomic weight or relative atomic mass -still in amu, carbon 12, 14 -not mass of one atom, is weighted average of all isotopes -on periodic table -1 proton/neutron = 1 amu -1 gram = 6.02 x 10^23 amu or 1 mol amu
structural formula
-give structure of benzene -basically lewis dot structure
ionization energy
-how hard it is to make atoms into cations (take away electrons); energy required to remove an electron to make an atom positive -increases as go to the right since protons pulling on electrons more (more protons); alkaline metals want to fill octet by getting rid of electron -as goes down periodic table decreases because of electron shielding (electron further from the nucleus) -nuclear charge- more protons in nucleus more of a pull on electrons -effective nuclear charge (Zeff)= nuclear charge(Z) - effects of shielding (s) -effective nuclear charge (Zeff) is like net force 3 is nuclear charge (number of protons) - 2 electrons = effective nuclear charge -easier to remove the first oxygen electron compared to nitrogen because oxygen has an up and down spin, so that the electron is being repelled
atoms in a mole
-6.02 x 10^23 -Avogadro's number
mass spectrometry
-can be used to look at isotopes, find average atomic mass, look at elements in a sample abundance times mass + abundance times mass .... = average atomic mass -abundance is decimal -look at atoms in a molecule or fragments in micromolecules
fundamental elements of an atom
-proton- in nucleus, defines the element, on periodic table ranked on atomic number (number of protons); positive charge -electron- chemical characteristics; negative charge -neutron- mass; no charge -protons/neutrons = nucleus of atom
structural formulas
-give info on how atoms are connected in space in a molecule (pic on right) -dashed line means behind main element -wedge means in front of main element -2 dots are lone pair that are not involved in covalent bonds
valence electrons and bonding
-for metalloids, last s block or d block can give up electrons in different combinations, resulting in different charges
characteristics of covalent bonds
-are the opposite, they don't dissolve easily, they have low melting points, and are not conductive. They are also usually gases or liquids, and any solids are relatively soft. However, diamond and quartz are two covalent compounds that are extremely hard, so there are some exceptions
molecular formula
-number of elements in a molecule -benzene- C6H6, still 1 to 1 ratio
electronegativity
-when atom part of a covalent bond, how much does the atom want to hog the electrons -as go from left to right increases because ions want to fill octet -as go down periodic table, atomic radius increases so shielding increases and electronegativity decreases -covalent bonds: when there is a difference in electronegativity between 2 atoms in a compound then polar because there is a partial positive and partial negative charge in the compound -if difference greater than 0.5 considered polar based on pauling scale -if partially negative then more electronically dense than partially positive atom -ionic bonds: in NaCl, Cl- so strong that Cl ion steals electron, getting a -1 charge for Cl
structure of atom
-held together by positively charged protons and negatively charged electrons (electrostatic attractions)
John Dalton's atomic theory
-first complete attempt to describe all matter in terms of its atoms and its properties -elements are made of extremely small things called atoms -atoms of given element are identical in size, mass, etc. -atoms of dif elements differ in size, mass, etc. -incorrect because of isotopes -atoms can not be subdivided, created, destroyed -untrue- protons/neutrons -atoms of different elements combine in simple whole-number ratios to form chemical compounds -in chemical reactions atoms are combined, rearranged, or separated -first attempt to describe all matter in terms of atoms and their properties -based his theory on law of conservation of mass and law of constant composition -law of constant composition- pure compounds always have the same proportion of elements- NaCl always has 1 Na and 1 Cl
parts of mass spec
-ionizer (vacuum)- insert sample, hit with electrons, pull electrons away from sample (cathode ray tube) -mass analyzer (negative electric field to move electrons into it), magnet bend path ions, if really heavier harder to make corner -detector- electron multiplier (plate, as electrons hit it, spawns more electrons that hits next plate to strengthen charge, get signal that is amplified, sent to computer) -heavier element farther to left
alkali metals
-soft, silvery, very reactive, react with water, so reactive that never found pure in nature -hydrogen exception in group 1 (nonmetal), not considered alkali metal -so reactive cause only need lose 1 electron to get octet
graph of mass spec
amu on x axis, intensity on y axis
drawing ionic bonds if not reacting yet
-not reacting yet but know there is an electrostatic attraction because of the positive/negative charges
ball and stick model
-balls= atoms -sticks=bonds -easier to see geometry of compound
noble gases
-group 18 -colorless -unreactive
deposition
gas to solid
empirical formula
-ratio of elements in a molecule -benzene- CH - 1 carbone per 1 H
alpha particles
helium nucleus, 2 protons 2 neutrons, no electrons
electron affinity
-energy absorbed/released when adding an electron -energy is released when nucleus has an effective nuclear charge on the added electron (not forced to occur) -generally, left to right the Zeff increases so that electron affinity increases (more energy given off) -nitrogen doesn't follow the trend since has 3 unpaired electrons, takes energy to put up spin and down spin electrons together -doesn't work for Ne and Be because effective nuclear charge = 0
writing out elements
isotope notation- mass number(A) (Z+N) over atomic number then element -if neutral the atomic number(z) = # electrons -element-mass number, carbon-12 or carbon-13
atom
most basic unit of an element
characteristics of ionic compounds
-Ionic compounds dissolve easily, have high melting points, are conductive, and non-malleable
sublimation
solid to gas
isotopes
-atoms of an element that differ in number of neutrons
period
horizontal row on periodic table
Section 2
(50 cards)
ferric
iron (III)
flame test
-heat excites electrons, moves them to a higher energy state, emission light color helps determine what compound it is
ernest rutherford
-predicted would go straight thro cause electrons spread out -showed all atoms have tiny, dense positively charged centers and mostly empty space -proposed nuclear model of atom -dense center, empty space -alpha particles - 2 protons, 2 neutrons -used gold because extremely malleable
photoelectric effect
-shine right type of light at right frequency, "collision between electron and photon" and electron go to higher state -focus on metals for this -freed electron called photoelectron, has kinetic energy based on equation
Niels Bohr
-based on assumption that electrons travel in special shells or orbits -explained the hydrogen spectrum in terms of electron absorbing and emitting photons -supported planetary model -thought electromagnetic radiation was quantized because e could only be found by the equation E=hv -quantized- only specific amount allowed -atomic line spectra -thought electrons can only be found in specific shells -energy level diagram -didn't explain why some lines are more intense than others
standard atomic mass
-mass of a particular molecule -add up protons and neutrons of different elements in compound as given
kinetic energy
K=1/2mv^2; 1 photon creates one photoelectron -m=mass (kg) -v=velocity (m/s) -k= kinetic energy (J)
infrared
molecular vibrations
polyvalent
-element able to form different cations like Fe -can not refer to as __ ion, must specify charge -indicate with roman numerals -transition metals
polyatomic ions
-contains more than one atom -molecule that has gained/lost electrons -put parenthesis around ion when cross-multiplying charges
XPS
-x-rays higher in frequency and energy than UV so provides enough energy to eject core electrons
relative atomic mass
-weighted average of molecules (use values from periodic table) -H2O, go to periodic table, do average atomic mass of hydrogen x 2 + average atomic Mass oxygen
cupric
-copper (II)
ferrous
iron (II)
higher frequency wavelengths
(violet) get bent more by water particles (acting as the prism) than lower frequency (red)
chromic
chromium (III)
spectrophotometry
-used to determine the concentration of solutions -darker solution absorbs more light -put sample of unknown molarity in spectrophotometer, absorbance is measured (0 means all light passes through- 100% transmittance, 1 means all light absorbed 0% transmittance) -Beer-Lambert law- A=ϵlc -A= absorbance (unitless) -e= molar absorptivity constant (M^-1cm^-1 -l = path length (cm) -c = concentration (M)
energy of photon
= kinetic energy + work function Φ -work function= min energy needed to free electron -energy of photon must be greater than work function for electron to be freed (creating photoelectron)
Max Planck and Albert Einstein
theorized that electromagnetic radiation behaves as photon and wave
Leucippus and Democritus
came up with idea that atomos make up stuff -iron atoms hard cause stuck together with hooks -clay atoms soft and stuck together with ball and socket joints
1 lone pair and 4 clouds
trigonal pyramidal 107 degrees
eugen goldstein
found canal rays in cathode ray, went opposite direction as electrons so must be positive charge in matter
naming monatomic anions
-add -ide to end -H^- = hydride
3 clouds no lone pairs
trigonal planar -all 120 degrees
axial positions
perpendicular to the trigonal plane (above equator)
5 clouds (2 lone pairs)
T shaped
spectroscopy
-different forms of electromagnetic radiation interact with molecules and atoms differently -this interaction is called spectroscopy -different types depending on frequency of light (UV-Vis, infrared, spectrophotometry) -photons carry discrete amounts of energy called quantum
infrared spectroscopy
-lower energy transmission in the infrared region can make molecules vibrate (can not make them jump energy levels) -energy required to change the vibration of a particle is fixed -can use to determine type of bonds present in a molecule -each bond vibrates differently
naming ionic compounds
-cation before anion -include charge if cation is polyvalent -net charge of zero -lowest ratio, like not Na2Cl2 is NaCl -cross charges -to decide charge of transition metals look at number needed to make atom
Predicting charges for monatomic cations/anions
-use periodic table -period- rows -family- columns -charges only apply to ionic bonds not covalent -gain/lose electrons to get full octet -groups 1, 2, 13, and 14 lose electrons -carbon only exception, sometimes gains electrons -groups 15-17 calculate number of electrons by doing 8 - electrons gain
werner heisenburg
-impossible to know momentum and location of electron -quantum theory- atoms have properties of waves and particles, orbitals- places where electrons most likely to be (cloud/quantum model)
6 clouds (2 lone pairs)
square planar
2 lone pairs 4 clouds
bent 104.5 degrees
JJ Thomson
find mass of rays (cathode ray), decide not rays in tube but negatively charged particles (corpuscles or electrons) -plum-pudding model -cathode ray tubes- most air evacuated, voltage goes from cathode to anode -phosphors painted on after anode, sparks when hit by cathode ray -able to find mass to charge ratio of stuff, find its smaller than H nuclei -decide stuff must be part of an atom (within all atoms cause kept changing material in cathode ray)
6 clouds (1 of which is lone pair)
square pyramidal
5 electron clouds
trigonal bipyramidal
3 clouds 1 lone pair
-bent -angle less than 120 degrees
equatorial positions
parallel to equator
microwaves
molecular rotations
light
-electromagnetic radiation- way energy travels through space -frequency= number full wavelengths get in a second, inverse of period (s) -c=lambda times v -lambda= meters -v=hertz -period of a wavelength- 1/frequency = seconds -c is a constant -mass and light originally seen as 2 different things- matter particles with mass and a known position, light is massless and position can not be determined -Max Planck found that matter only absorbed certain energy, challenged idea that energy can always be transferred; found that energy is quantized, only transferred in pockets of size hv called quantum, so light not just a wave but also a particle -photon- quantum/particle of light- E=hv\
5 clouds (3 lone pairs)
linear
5 clouds (1 of which is lone pair)
seesaw
UV-vis
-when hydrogen atom absorbs a UV photon cause electron to go to higher unstable energy level (movement called a transition), when goes to ground state emits light (example of a model of this) -larger the transition more energy emitted (why level six gives off purple light) -energy transitions of each electron different for each species, use emission spectrum to identify it -get valence electrons to eject
PES
-needed to understand the structure of molecules -needed to understand elements and compounds -can be used to explain why electron configuration works- electron emission spectrum can be used to find ground state of that electron, build shells in this way This shows that energy of energy of an electron is quantized but this equation only works with hydrogen -successive ionization energy increases because more positive an ion is, more energy is required to remove the electron (need both the first ionization and second ionization energy to remove the 2nd electron -core electrons require more energy to remove than valence -E=hv means that light with higher frequency has a higher amount of energy
Chromous
chromium (II)
stannic
tin (IV)
4 clouds
tetrahedron 109.5 degrees
stannous
tin (II)
cuprous
copper (I)
6 clouds
octahedral
Section 3
(50 cards)
remove core electrons
-any frequency of light that can remove an electron from the first subshell can do so from any other shell -hv=W + KE -hv=E -W = work function (different from ionization energy because work function is the energy required to remove an electron from a metal, ionization energy is the energy needed to remove an electron from an atom) -KE = kinetic energy
van der waals equation
-an^2/V^2 accounts for measured pressure being less than accurate, n x b accounts for measured volume being more than accurate
law of partial pressure
gas molecules behave independently so that adding two gases together does not change partial pressure of each gas; works only with ideal gases -pressure from 1 gas in mixture -P1+P2... = Ptotal -called Dalton's law of partial pressure -if mixture of gases and know total -P of gas 1 = (moles of gas 1/total moles of gas) x total pressure
heat and temperature
-heat (q) is thermal energy transferred from a hotter system to a cooler system q= m x C x delta T -C= specific heat capacity -m = mass (grams) -T = temperature- convert to K or celsius depending on C -sign or q dependent on delta T -temperature doesn't change if add substance of same temp- why can use melting point to define substance -need know number of molecules in system and heat capacity of system to find change in temp -temperature measures the average kinetic energy of molecules
Erwin Schrodinger
-showed electrons can be thought of as waves and particles, lead to Heisenberg's Uncertainty Principle (can't know electron's position and velocity at same time) -shows Bohr's model is actually a probability model
noble gas configuration
-take the noble gas immediately preceding atom/ion, put in brackets, do electron configuration after this point -silicon- [Ne] 3s^23p^2 -all electrons after the noble gas are valence electrons -Calcium 2+ has electron configuration of [Ar] so you know this ion has a full octet
peroxide
-A peroxide is a compound that contains an oxygen-oxygen single bond. If you aren't sure if you have a peroxide based on the molecular formula, try drawing the most likely Lewis structure. In general, peroxides are not especially common because the oxygen-oxygen bond is a pretty weak (and reactive) single bond
molecular mass
mass of one mole of compound
Empirical formula based on mass composition
-given percentage of element in molecule, assume 100 total grams, so percent is grams of element, find moles, divide by smaller amount of moles get ratio in empirical formula
orbitals
-Heisenberg uncertainty principle states that it is not possible to know both the position AND the momentum of a particle with complete accuracy -orbital- probability function around the nucleus where electron will most likely be found -subshell s contains 1 orbital, subshell p contains 3 orbitals, subshell d contains 5 orbitals, subshell f contains 7 orbitals
Electron configuration with d block
-principle energy level-1
temperature
average energy of molecules in system (energy/particle)
combustion
CxHx + O2 = CO2 + H2O
irreversible reaction
-requires a lot of energy to go the other way -usually when just have arrow (pic above) -harder to break bonds of product (more stable, require more energy)
hydration
ion is surrounded and stabilized by water molecules
zeroth law of thermodynamics
-no heat is transferred between 2 objects in thermal equilibrium (both objects have same temp) -why thermometers work
heat of fusion/vaporization
-once at right temp find heat needed to change phase -Q= mL -mass = m -L = latent heat of fusion/vaporization; heat needed change phase J/g
heat capacity
-tells how much energy needed to change temp of a given substance assuming no phase change -specific heat capacity (C or c) energy needed raise temp of 1 gram of substance by 1 degree celsius -units of J/grams x celsius -4.18 J/grams x celsius for water -molar heat capacity- (Cm or Cmol) thermal energy needed to raise one mole of sub by 1 degree celsius/K -units of J/mole x celsius -specific heat capacity dif btwn substances because of breaking/creating bonds
volatilization gravimetry
separate components of mixture by heating or chemically Decomposing substance, take out volatile substances so can measure mass -BaCl2⋅2H2O(s)→BaCl2(s)+2H2O(g) -heat up water, become water vapor, find moles of water (product) use equation to find amount of hydrate (reactant)have, find grams, do percent yield to find how pure substance is (amount hydrate / total mass) -Surface area is always a factor when removing volatiles from a sample. Having a higher surface area will increase the rate of evaporation. You can increase the surface area of the sample by spreading your sample as thinly as possible on the heating surface or breaking up any larger chunks of solid, since moisture can get trapped inside the chunks.
dissolution
solute placed in solvent and forms solution
Bohr's model of hydrogen (1 proton and 1 electron)
-proposed planetary model- electrons orbit nucleus like planets and sun -quantization- with emission spectrum knew that only specific values allowed of light -made assumption electronic structure of atom quantized (electrons can only orbit in specific shells and not in between the said shells) -r(n)=n2⋅r(1) -n = positive integer -r(1) = smallest allowed radius for hydrogen -r(n) = negative number always with r(1) being the most negative -if get energy equal to the energy difference between the initial and final energy levels then electron jumps to an excited state, emitting light as return to ground state -model only works if atom has 1 electron -unable explain zeeman effect -why some lines more intense than others or spectral lines split up in presence of magnetic field
neutralization reaction
-acid and base react to produce water and salt
internal energy
-some of energy of all particles in system (potential, kinetic, bond) -can not be created/destroyed, only change -equals q + w -work on system -heat = q -heat is the transfer of energy -heat transfers to surrounding then q - -heat go to system q + -make sure q in joules and work in atm/L
precipitation
-when chemicals in a solution react to make a solid -nitrates dissolve easily -silver + bromine + chlorine + iodine = precipitate -molecular equation- normal, balanced equation -complete ionic- list all ions separately -net ionic- leave out spectator ions -supernatant- the clear liquid that floats above the precipitate
analyzing PES
-x axis reversed since nucleus on left hand side on origen, show that as move to right electrons farther away and require less energy -only thing change relative number of electrons is number of electrons in the sample -only works for pure? -shows the copper/chromium exceptions -when see 2 peaks for a subshell, see the spin -mixture of element- binding energy (x axis) vs intensity -peaks not number of electrons in orbital but show abundance, if 1 s1 peak is higher than another then that element has a higher abundance -element in mixture with greater atomic number require more energy to remove e-
based on the law of conservation of mass
the number of molecules on the reactant side and product side must be equal.
diagmagnetic
-all of electrons are paired -not attracted by a magnetic field
auto-oxidation reaction
-AKA disproportionation reaction -single element is oxidized and reduced -3ClO−(aq)→ClO3−(aq)+2Cl−(aq)
Oxidation number/Redox (Oxidation Reduction)
-hydrogen = 1+ -oxygen = 2- -atoms have zero (no hogging of electrons) -if look at electronegativity of elements in compounds then whichever one is stronger will gain electrons, increasing negative charge -write sign after number -In CO2 O has greater electronegativity so each oxygen gains 2 electrons (2 bonds), C must lose electrons O gains -oxidized = lose electrons (OILRIG) -reduced = gains electrons -half reactions = focus on elemental components of reactions -CH4 + 2O2 = CO2 + 2H2O -C^4- = C^4+ + 8 electrons, carbon oxidized -H4^+ +2H2^+ -2 O2 + 8 electrons = 4O^2-, oxygen reduced -electrons taken from carbon -if add half life reactions get overall reaction, multiply if need be -used to keep track of how many electrons an element has, not always same as charge -monatomic ions (single ions) have number equal to charge -fluorine = -1, hydrogen = +1, oxygen is usually assigned a −2 oxidation number (except in peroxide compounds where it is −1) -oxidizing agent - AKA oxidant, gain electrons and is reduced by another element -reducing agent - AKA reductant, lose electrons and is oxidized by another element -combustion, single replacement, disproportionation reaction
balancing chemical equations
-need same number of molecules on both sides (reactants/products) -put coefficients accordingly -if decimal then double -save single elements for last -make a table
pressure
-when gas particles bounce off container, make force/area so create pressure -slower particles mean less force so less pressure pressure= force/area
x-ray
core electron transitions in atoms
Predicting if a single replacement reaction will occur
-which cation/anion is the most reactive? If it's the single element that is more reactive then single replacement will occur
visible/ultraviolet
valence electron transitions in atoms and molecules
ideal gas law
PV=nRT -pressure in ATM -V is in L -n is in moles -T is in K -volume decreases then area decreases, pressure increases
Electron configuration with f block
-principle energy level - 2
gravimetric analysis
-lab tech used to determine mass / concentration by measuring a change in mass -analyte is substance trying to quantify
Non-ideal behavior of gases
-assumptions of ideal gas law- assume ideal gas, assume don't attract/repel each other, assume volume of gas inconsequential -compressibility constant- used to see how ideal a gas actis, when Z =1 then is acting as ideal gas -high pressures- gas molecules get crowded and empty space between molecules decrease; V in ideal gas law is volume gas has to move around -Z = PV/nRT -gas ends up taking up more space than predicted, increasing V so that Z is greater than 1 -get worse as gas becomes compressed, so higher the pressure bigger Z is -Low temperature and intermolecular forces -when have forces molecules effectively slowed, hit sides of container less so V less, make Z less than 1 -prominent at lower temps cause molecules don't have energy to
bohr model radii
-rn = n^2r1 -r1 = constant (5.3 x 10^-11) for -n= energy level -rn = radius at n energy level -can not get value in between positive integers of n
double replacement reaction
-swapping cations of reactants -usually solvent is water and reactants are aq
how PES works
-radiation source causes electrons to be ejected from sample -electrons travel through the hemispheric analyzer, where KE is measured and recorded -Kinetic energy analyzer -need large sample so electrons from all energy levels can be analyzed -expose sample to electromagnetic radiation, electrons shoot off -once electron ejected from atom passes through hemispheric analyzer with 2 voltage plates (one negative voltage other slightly negative) -need measure voltage needed to move electron across pathway -can do by doing: -if KE too high then crashes into negative voltage hemisphere -if voltage too high can crash into slightly negative hemisphere -work function involved with removing electrons when sample in solid state, add 1 additional energy level that must be overcome (don't have this with gas phase)
carbonic acid
-in gas form make CO2 gas -carbon bubbling (bubbling = H2O) result in carbonic acid
precipitation geometry
use precipitation reaction to separate parts of solution by incorporating it into a solid -precipitate and precipitating agent are what is added to causes precipitation Reaction -add precipitate, find mass of precipitate, do balanced equation, convert mass precipitate to moles, use stoich to find moles and then grams of compound under subject, find mass percent of it (grams/total grams of original solution) -If you have time, one way to check for water in the sample is to recheck the mass a few times during the end of the drying process to make sure the mass is not changing even if you dry it longer. This is called drying to constant mass, and while it does not guarantee that your sample is completely dry, it certainly helps! You can also try stirring up your sample during the drying process to break up clumps and increase surface area. Make sure you don't tear holes in the filter paper, though!
energy needed to make liquid ice water
-use mL + delta t times mass times C = total change in energy
bohr model energy
-En = E1/n^2 -E1=energy associated with an electron and the lowest energy level of hydrogen -2.17 x 10^-18 J (negative value) -E1 must be in eV -n is an integer (energy level) -En = energy at that energy level
First Law of Thermodynamics
-thermodynamics is the study of temperature and its properties -energy can not be created or destroyed, can only be transformed from 1 form to another
paramagnetism
-when there is 1+ unpaired electron(s) (spin up but not spin down) -attracted to magnetic field -if have a balance, 2 substances in balance, turn magnet on will attract metal, tip scale -gases are never attracted by a magnetic field
limiting reagent
-make sure equation is balanced -convert grams to moles -find how many moles need, whatever don't have enough of is the limiting reagent -use limiting reagent and stoich to find moles/mass of products -find how much reactant left after reaction do amount used - initial -theoretical yield is the amount of product that can be produced -actual yield -sometimes side reactions occur resulting in products don't want -percent yield = actual yield/theoretical yield x 100 (grams not moles)
stoich
-using a balanced chemical equation to find the amount of a product/reactant -balanced equation gives mole ratio -make sure equation is balanced -convert products/reactants to moles and then do mole bridge (make sure units cancel out) -reactants = reagents
Molecular mass/weight percentage
-mass of carbon / total mass of molecule
Section 4
(50 cards)
calorimeter
insulated container contains thermometer, stuff in calorimeter system -insulation prevents heat from escaping
gibbs free energy
-if exothermic put energy on product side -if endothermic put energy on reactant side = delta H - T x delta S -spontaneous nothing to do with time, just will reaction occur on its own -less than zero then spontaneous (called exergonic) -at constant temp. and pressure -t= kelvin, s and h are of system -g final - g initial = delta g also -since delta h and delta t don't change much with temp, can assume constant at all temps (except with phase changes) -delta h given in KJ, delta s in J -STANDARD TEMP = 298 K -less than 0 spontaneous -greater than 0 nonspontaneous -0 = at equilibrium
second law of thermodynamics
-entropy in universe always increasing -why ice can't spontaneously form -there can not be any spontaneous heat from cold to hot- faster particles hit slower particles, causing a transfer of heat -any spontaneous process increases the disorder of the universe and does not require work to occur- thermodynamically favorable -if not spontaneous requires work to occur -Q2/T2 - Q1/T1 = positive number
properties of acids
-taste sour, react with active metals to make H2 (corrosive) -react with carbonates to produce a gas
calorimetry
science of measuring the change in heat associated with a chemical reaction
delta g zero =
- RTlnK -delta g zero = change in free energy at standard conditions -can be used to find equilibrium constant -T = kelvin -delta g in J
covalent bond
2 atoms each contribute an electron to the bond
polyprotic acid
-loss of 2nd or third hydrogen will occur less readily than the lost of the 1st -as acid become more negative harder to remove hydrogen -only focus on 1st dissociation step when solving for pH -when asked to find pH of second dissociation need be make the first dissociation and solve for all molarities, make a second dissociation and plug in the value you know, solving for the ones you don't
indicators
-changes color with change in pH range -want indicator changes color at equivalence point
kinetics
-study of the rates of reactions -activated complex- the transition state of a reaction; when bonds breaking and forming at top of energy diagram curve -catalyst- is used by but is not consumed by the reaction; makes reaction faster -speed up reaction if use catalyst, increase concentration of reactant, increase temperature (increase collisions), increase surface area
strong acid strong base
-make net ionic equation, label moles, find limiting reagant and reactant left over, do dissociation and find molarity, do -log to find ph MV=MV neutralization short-cut -M is M of OH- or H+ -good for strong/strong
autoionization of water
-under the right circumstances, a water molecule grabs another hydrogen proton -the water molecules still have the same number of electrons -cause plain water to have hydronium ions -autoionization- reaction between molecules of the same substance to produce ions -kw = 10^-14 at 298k -[OH-][H+]=kw -H+ = OH- at neutral -water is amphoteric- can act as an acid or base so can react with itself -H2O + H2O = OH- + H3O+
zero order
-[A]t and t graph gets a linear line of slope -k
ways to get a buffer solution
-add weak acid and salt with CB -weak acid and strong base
buffering capacity
maximum concentration of hydrogen ions that a buffered solution can neutralize- found through titration
buffers
-buffers solutions resist changes in pH -contains weak acid + conjugate base or weak base + conjugate acid -cause weak not all dissociates, what doesn't dissociate become source/sink of protons
strong bases
-group 1 + OH- -Ca, Sr, Ba + OH-
salts
-strong acids dissociate completely, CB so weak does not influence pH (like Cl- from HCl no significant influence on pH)
delta g =
= delta g standard change in free energy (under standard conditions) + RT ln Q -Q= reaction quotient- where we are in reaction, same form as K -T = kelvin -R = constant -delta g measured in KJ/mol, need to be converted to J
Kp
-equilibrium constant describing ratio of products to reactants in form of partial pressure -still ignore pure liquids and solids -Kp = Kc(RT)^ change in moles -change in moles = moles of gas product - moles of gas reactants -to convert molarity of gas to pressure use ideal gas law -using Dalton's law of partial pressure: if know ratio of products (1 x of oxygen gas for 2 x of hydrogen gas), can add x's to find the partial pressure of each gas (x + 2x= total pressure, solve for x)
sig figs and logarithms
-sig figs in of what taking log of is the number of sig figs in mantissa (whatever comes after the decimal point)
enthalpy
-H = E + PV -e= internal energy of system -p=pressure -v=volume -H = q when PV=0
coordinate bond
1 atom contributes both electrons for bond
rate of reaction
-change in concentration (M)/change in time (s) -should always be positive -use stoich to convert this to the rate of production of a specific product -rate of production/reaction can be different for each product/reactant
weak acid strong base:
-make net ionic equation, label moles, find limiting reagant and reactant left over, do dissociation, put M of acid/base and conjugate, do Ka/b and solve for OH- or H+ -at equivalence point find concentration of conjugate, show reaction with water, find pH (do Ka/b and stuff) -after weak acid neutralized strong conjugate base reacts to produce hydroxide ions, why ph is greater than 7 at neutralization point
strong acid
-HClO4, HClO3, HCl, HBr, HI, H2SO4, HNO3 -completely dissociate
Hess's Law
-total enthalpy change for a chemical reaction does not depend on the pathway it takes; depends on initial and final states -reverse direction then delta h of formation = - value -multiply reaction then multiply delta h value -should be able to add up steps to get overall balanced equation
Conjugate acid-base pairs
entropy
-measure of disorder of system; how many states a molecule can take on -higher probability that molecules be in disorder than order -state function- does not depend on pathway of reaction -sum of products' entropy - sum of reactants' entropy = delta S of reaction -if delta s positive then disorder increased -how calculate all state functions (enthalpy, gibbs free energy) -delta S= heat added to system / temperature at which was added -delta=Kln of number of states have (k=constant) -macro state- never talk about entropy of a single atom -"how much info needed to describe movement of particles"
heterogeneous eq
-different states of matter in equilibrium expression -do not include pure liquids (water) and solids in K expression
Equilibrium Constant K and the reaction quotient
-reversible reaction can go in the forwards or backwards direction -equilibrium is where the rate of the forward reaction equals the rate of the backwards Reaction -Kc=[A]^a[B]^b[C]^c[D]^d -solids and pure liquids not included -is equal to Q (the reaction quotient) at equilibrium -when molarity of products/reactants constant on graph then at equilibrium though still constantly reacting (dynamic equilibrium) -Q>Kc reaction proceeds in the backwards direction to make reactants -Q<Kc reaction proceeds in the forwards direction to make products
Small x approximation for small Kc (5% rule)
-if K really big can assume that x is negligible- once get answer make sure that x is less than 5% of the original concentration of the reactant -when K really small assume all reactant (M of product = 0) -when K large assume all product (M of reactant/products = what left after both reactants) react -if plug values found into equilibrium expression can check to see if answers close
properties of bases
-bitter, slippery, caustic (breakdown proteins)
pH, pOH
-alkaline=basic -p=-log, so pKw = -logKw -pOH=-log[OH-] -pH=-log[H+] -pH + pOH = 14 -as H+ increases by factor of 10 pH decreases by 1 -acidic solution pH< 7, basic >7, neutral = 7 -determine pH of diluted acid through M1V1=M2V2 -pH based on concentration and dissociation properties so weak acid may have a higher pH than a strong acid because of concentration
finding units for K
-solve for K units if plug in M for [] and M/s for R and solve for K -plug in molarities once you know rates of both reactants, plug in what rate equals, solve for k -k depends on temperature
Le Chatelier Principle
-if add reactant A more likely for collisions between reactant particles, cause increased creation of products (2nd reactant will slightly decrease cause didn't add any more and reacting more) -increase products then increase in reactants -endothermic reaction then if add heat, equilibrium shifts to products -exothermic reaction then if take away heat, shift to products -increase in pressure, equilibrium shifts to side with less moles of gas -adding a catalyst has nothing to do with equilibrium
Henderson - Hasselbach equation
pH = pKa + log (molarity of conjugate/molarity of acid or base after reaction) -HA = A- + H+ -when add OH- H+ disappears, equilibrium shifts to make more H+, pH increases dramatically -NaOH = OH- + Na -no shock absorber, pH increases dramatically -if add something to a buffer, make reaction and include the ORIGINAL MOLARITIES OF THE CONJUGATE AND THE ACID/BASE, have them react, see what's left and go from there
titration
-burette, erlenmeyer flask, indicator (phenolphthalein is pink with basic and clear when acidic) -standard solution (know volume, concentration) in burette -drip standard solution into flask containing acid/base
bond enthalpy
-energy it takes to break 1 mole of a bond in the gas phase -break bonds then add energy -always positive delta h -reverse = making a bond -always negative delta h -use to estimate delta h of reaction -draw lewis dot structure of all compounds in molecules -look at bonds broken/made and bond enthalpies of these bonds -delta h rxn = energy to break bonds (positive) + energy to make bonds (negative)
weak acid-base
-weak acid HA with conjugate base A- has Ka= [H3O+][A-]/[HA] -larger Ka stronger acid is -Kb= [BH+][OH-]/[B-] -Kb = base dissociation constant; extent of ionization of weak base, larger is stronger base -weak acids/bases only partially dissociate; ionization reaction is reversible -COOH -calculating percent dissociation -write equation, Ka expression, RICE, get concentration H+, use formula
reactions in equilibrium
-used to find M of products/reactants at equilibrium -doesn't mean same for all -only true at specific temperature -k less than 1 backwards reaction favored -k greater than 1 forward reaction favored -k = then equal M of products/reactants -at equilibrium forward/backwards reaction same rate
Acid strength, anion size, bond energy
-more stable conjugate base stronger acid -lower pKa stronger acid, as -as go down periodic table size of anion increases, stabilizing conjugate base -bigger anion more space negative charge is spread out, better stabilizing negative charge result in stronger acid -more electronegative as go along period more stable conjugate base so stronger acid -weaker bond strength more likely dissociate, result in higher Ka or lower pKa
rate laws
-given chart of reactant molarity and initial rate, do calculations on trials when other reactants remain constant -if molarity double and rate doubles then first order -equation: final rate/initial rate = molarity final^x/molarity initial^x, solve for x to get order -R=K[A]^x[B]^x -R=rate of reaction (M/s) -k=rate constant (depends on temperature; units change) -[A]=molarity of A -x=order -add up all X get overall order -unlike with equilibrium expression, X not stoich points
relationship beteen Ka and Kb
Ka times Kb = Kw -pKa + pKb = 14 -Ka = acid dissociation constant -Kb = base ionization constant -only works for conjugate acid/base pairs -Kw from autoionization of water, Kw = molarity of OH- times molarity of H3O+ which always equals 10^-14 -bigger Ka means higher molarity of hydronium ions, means that strong acid and weak CB
solid dissolves and an ion or cation reacts with the solution
make a synthesis reaction to form a complex ion. Add the dissociation reaction and complex ion reaction to get the overall reaction, multiply the ks to get the overall keq -use this net reaction and overall keq to find the molar solubility of the solid (2nd picture below)
Arrhenius Acids and Bases
-arrhenius acid- any species increases concentration of H+ in solution -dissociate HCl then increase H+ in solution cause H+ present -no free H+ floating in solution -need H+ in formula -arrhenius base- any species increases concentration of OH- in solution -need OH- in compound -H+ + H2O = H3O+ -in neutralization reaction, an Arrhenius acid and base react to produce salt and water -limits in Arrhenius definition -only describe acid-base in aq solution -acids/bases not just H+/OH-
standard enthalpy of formation
-amount of heat lost or gained when one mole of a compound is formed from its constituent elements
Ksp
rate of dissolution is equal to rate of precipitation -make dissolution equation, do rice table, molar Solubility = x, find Ksp -given Ksp find solubility- do rice table, solid no influence, do Ksp expression, solve for X, have molar solubility of solid, convert to solubility
Bronsted-Lowry definition of acids and bases
-acid is a proton donor -base is a proton acceptor -NOTE: Proton same as hydrogen ion because most common isotope has no neutrons and no electron -acid, base, conjugate acid, conjugate base
pressure volume work
-work is energy required to move something against force -gases do expansion/compression work according to equation: w=-PdeltaV (atm and L) -P is P external -units = J -work on surroundings internal energy decreases, on system than increases -A SYSTEM CAN DO WORK BUT CANNOT CONTAIN WORK -101.325 J = 1atmL -volume increases negative work -when constant volume (bomb calorimeter) then no work can be done -work due to phase change so insignificant that you don't have to worry about it -work = Force x Distance, since force = pressure x area x distance or pressure delta V
Section 5
(50 cards)
Voltage as an intensive property
-Voltage does not change if the number of moles of electrons changes
polar covalent bond
electrons getting pulled to spend more time at one side of Compound; dif in electronegativity greater than 0.5
Maxwell-Boltzmann Distribution Curve
-temperature is proportional to average kinetic energy in a sytem -some molecules in same condition go faster than others - -higher average K energy = smaller peak -same number of particles so area same even if change temperature -most probable speed of N2 at room temperature if 422 m/s -look at peak of curve
Ionic Bonds and Coulomb's Law
-ionic bonds hold cations and anions together (NaCl) -how ions arranged influence solubility, melting, boiling points -electrostatic force- force between 2 charged species -Fe =kq1q2/r^2 -r= sum of ionic radii -melting point increase as Fe increases (more force btwn ions then more force to break them)- look at charges and radii to explain which one higher melting point
arrhenius equation
-k=Ae^-Ea/RT -k= rate constant -a= frequency factor pre-exponential factor -takes into account frequency/orientation of collisions -f= -Ea/RT -Ea = J/mol ln(k2/k1)= -Ea/R(1/T2 - 1/T1) -use to find Ea of a reaction
redox titration
-reactants are different colors but products (as ions) are colorless -by adding a known amount of a certain concentration of a reactant, when the solution becomes slightly colored then is end point because some of the reactant is not reacting -find moles of titrant, find moles of analyte using stoich -divide moles of analyte by volume of original analyte, get molarity
Galvanic Cell
-device in which chemical energy is transformed to electrical energy -a spontaneous redox reaction is used to produce a current -if able to make electrons go through a wire creates current and power, resulting in useful work -separate 2 reactants so electrons must travel through a wire -need salt bridge because if a solution becomes too positive then anode will not "want" to create products -anode= negative part of battery -cathode=positive part of the battery -standard electron potentials- relative to hydrogen, how much does this ion want to grab its electrons -with voltage switch sign if need to but never multiply the e cell standard -only works under standard conditions
Common types of redox reactions
-combustion -disproportionate reaction- reaction in which a single reactant is oxidized and reduced -single replacement or displacement reactions
free energy and cell potential
-delta G = -nFE -E = cell potential -n = moles of electrons transferred in redox reaction -F=constant (charge carried by one mole of electrons)
disproportionate reaction
-when a substance is oxidized and reduced in the same reaction
delta g and E
-delta G = -nFE -E = cell potential -n = moles of electrons transferred in redox reaction -F=constant (charge carried by one mole of electrons)
Ecell and sponteity
-if Ecell is positive then spontaneous -if Ecell is negative then nonspontaneous -if E cell is 0 then in equilibrium
nonpolar covalent bond
electronegativity btwn atoms in compound so small or nonexistent that electrons not pulled to one molecule (no partial positive/negative charge); dif in electronegativity less than 0.5 (based on pauli scale)
what is a redox reaction
a chemical reaction that involves the transfer of electrons between 2 species -can tell if it is a redox reaction if the oxidation number of an element changes from reactant to product
standard conditions
-pure solids -1.0M concentrations -1 atm -298K
common types of redox reduction
-combustion -disproportionate reaction- reaction in which a single reactant is oxidized and reduced -single replacement or displacement reactions
spontaneity and E
-if Ecell is positive then spontaneous -if Ecell is negative then nonspontaneous -if E cell is 0 then in equilibrium
concentration cell
-cell that has same electrodes on both sides -left side less concentrated, right side bigger concentration -less concentrated oxidizes to increase M -bigger M reduces to decrease M -they want equal M How to make Q in Nernst Equation -standard E equals 0 -when concentrations are equal E = 0
metallic bonds
metals very happy to share electrons; metals create electron pool that positive metals attracted to, cause of sea this allows for conductivity
oxidation and reduction
-when occurs in solution the electrons transfer directly and no useful work can be obtained from the chemical energy involved in the reaction -when oxidizing agent physically separated from reducing agent then electrons must flow through a wire = useful work -instead of thinking about covalent bonds as partially positive or partially negative, pretend as if each element in a compound takes electrons, acting ionically -when writing oxidation states or ion charges convention is to put charge after number (so not a +3 charge but a 3+ charge) -oxidation/reduction agent- loses electrons -reduction/oxidation agent- gains electrons -hydrogen ion always positive 1 charge -oxygen has a 2- charge unless in a peroxide, then a 1- charge -fluorine negative one charge, oxygen has a 2+ oxidation state when OF2 -atoms have an oxidation state of 0 -compounds should have an over neutral charge -polyatomic ions have an overall oxidation state equal to the charge of the ion
catalyst
-not consumed in reaction -decreases Ea so more molecules enough energy to react, increase reaction rate -doesn't influence energy of reaction
standard cell potential
-E when cell is under standard conditions -pure solids -1.0M concentrations -1 atm -298K
electrolytic cell
-an electric current is used to drive a nonspontaneous redox reaction -equals negative standard E total -current = charge/time -C/s = A -use electrical energy to produce chemical change -electroplate - cover electrode with solid
get slope of -Ea/R
-lnK = lnA + -Ea/R (1/T) -lnK vs 1/T get slope of -Ea/R -do rise/run to get slope
heterogeneous catalysts
are catalysts that are in a different phase than the reactants. For example, the catalyst might be in the solid phase while the reactants are in a liquid or gas phase.
elecrolysis
-involves forcing a current through a cell to produce a chemical change for which the cell potential is negative
Shorthand notation for galvanic cell
-ANOX- anode oxidation -RED CAT- redox cathode -solid anode l ion ll ion of cathode l solid cathode -l = phase boundary -11=salt bridge
formal charge
-formal charge = number valence electrons in free atom - number valence electrons in bonded atom (number of bonds/2 + number free valence electrons on atom) -want to equal zero, rearrange lewis dot structure if need be to get 0 formal charge
Balancing Redox Reactions in basic solution
-follow steps as in acidic solution -add hydroxide ions to reactants and products, should neutralize hydrogen ions to get water
elementary rate law
-take coefficient from balanced equation for superscript -cause more particles then more collisions, increase rate of reaction -unimolecular reaction- 1 molecule in reactant Rate=k[M]^1 -bimolecular reaction- 2 molecules reactant Rate=k[M1]^1[M2]^1 Rate=k[M1]^2 -termolecular- 3 molecules collide/react at same time Rate=k[M1][M2][M3]
voltage as an intensive property
-Voltage does not change if the number of moles of electrons changes
first order reaction
-integrated rate law: ln[A]t - ln[A]o = -kt -rearranging in y=mx + b format= ln[A]t = -kt + ln[A]o -graph of ln[A]t vs time gets a linear graph with -k being the slope -0.693/k = half life of first order reaction -half life = time it takes for concentration of a reactant to decrease by half -never know if element is going to decay
Oxidation reduction
-instead of thinking about covalent bonds as partially positive or partially negative, pretend as if each element in a compound takes electrons, acting ionically -when writing oxidation states or ion charges convention is to put charge after number (so not a +3 charge but a 3+ charge) -oxidation/reduction agent- loses electrons -reduction/oxidation agent- gains electrons -hydrogen ion always positive 1 charge -oxygen has a 2- charge unless in a peroxide, then a 1- charge -fluorine negative one charge, oxygen has a 2+ oxidation state when OF2 -atoms have an oxidation state of 0 -compounds should have an over neutral charge -polyatomic ions have an overall oxidation state equal to the charge of the ion
shorthand for galvanic cell
-ANOX- anode oxidation -RED CAT- redox cathode -solid anode l ion ll ion of cathode l solid cathode -l = phase boundary -11=salt bridge
Resonance and Dot structures
-to make the nitrogen in NO3- have an octet, we can do a few things, all of these are resonance structures of each other (shown by double arrow in pic) -make second bond with 1st/second/3rd oxygen -all 3 are attempts to make lewis dot structure (not correct) -combine all three structures- dots show that bond is present but not as strong as a double bond
drawing dot structures
-find total number of valence electrons -add electron for negative charge -3rd period more orbitals available so can exceed octet -decide central atom based on which least electronegative (ignore H+) -make bonds and minus the electrons needed to do this from total valence -assign extra electrons to terminal atoms -H only get 2 valence electrons -if central atom doesn't have octet then make necessary bonds -put hydrogens on oxygens
Relating K to standard cell potential
-E standard = (0.0257/n) lnK -E standard = (0.0592/n) logK
ionic bonds electronegativity
one element actually steals electrons of another; usually when electronegativity difference is greater than 1.7
Nernst equation
-E = Estandard - (RT/nF)lnQ -as Q increases E decreases -at equilibrium E = 0
Nernst Equation
-E = Estandard - (RT/nF)lnQ -as Q increases E decreases -at equilibrium E = 0
galvaniv/voltaic cells
-a spontaneous redox reaction is used to produce a current -if able to make electrons go through a wire creates current and power, resulting in useful work -separate 2 reactants so electrons must travel through a wire -need salt bridge because if a solution becomes too positive then anode will not "want" to create products -anode= negative part of battery -cathode=positive part of the battery -standard electron potentials- relative to hydrogen, how much does this ion want to grab its electrons -with voltage switch sign if need to but never multiply the e cell standard -only works under standard conditions
collision theory
-molecules must collide to react -collisions must have the right orientation -collisions must create enough energy (at least activation energy)
electrochemistry
-the study of the relationships between electricity and chemical relations -includes both spontaneous and nonspontaneous processes
second order reaction
-graph of 1/[A]t and t gets a linear line of k slope
redox reaction
-a chemical reaction that involves the transfer of electrons between 2 species -can tell if it is a redox reaction if the oxidation number of an element changes from reactant to product
types of catalysts
enzymes, acid-base catalysts, and heterogeneous (or surface) catalysts
Electrolytic cell
-an electric current is used to drive a nonspontaneous redox reaction -equals negative standard E total -current = charge/time -C/s = A
surface catalyst
where the reactant molecules are adsorbed onto a solid surface before they react with the catalyst to form the product.
mechanism
-sequence of elementary steps through which a reaction proceeds -add up to get overall reaction -intermediate -molecule made in one step of reaction and consumed in next -must be consistent with overall rate -slow step is the rate determining step -fast time little impact on overall rate when add -The slowest step in the mechanism is called the rate determining or rate-limiting step. -An elementary reaction is a reaction that happens in a single step, with one transition state and no intermediates. -Reactions that involve more than one elementary step are called complex reactions
enzymes
are proteins that act as catalysts in biochemical Reactions.
Section 6
(2 cards)