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82 Cards in this Set
- Front
- Back
Define Lewis Acid |
An atom or molecule that can accept a pair of nonbonding electrons |
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Define Lewis Base |
An atom or molecule that can donate a pair of non bonding electrons |
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What does the Drago-Wayland equation describe? |
-delta H=EaEb + CaCb -delta H implies that the reaction gives off energy E's represent the electrostatic susceptibility while C's represent the covalent. Can be used to predict enthalpy change |
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VSEPR 2 atom 0 LP |
bent electron geometry linear |
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3 atom 0 lone pair |
trigonal planar electron geometry: trigonal planar |
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2 atom 1 lone pair |
bent electron geometery: trigonal planar |
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4 atom 0lone pair |
tetrahedral electron geometry: tetrahedral |
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3 atom 1 lone pair |
trigonal pyramidal electron geometry: tetrahedral |
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2 atom 2 lone pair |
bent electron geometry: tetrahedral |
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5 atom 0 lone pair |
trigonal bipyramidal electron geometr: trigonal bipyramidal |
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4 atom 1 lone pair |
seesaw electron geometry: trigonal bipyramidal |
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3 atom 2 lone pair
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t shape electron geometry: trigonal bipyramidal |
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2 atom 3 lone pair |
linear Electron geometr: trigonal bipyramidal |
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6 atom 0 lone pair |
octahedral electron geometry: octahedral |
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5 atom 1 lone pair |
square pyrimadal e geometry: octahedral |
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4 atom 2 lone pair |
square planar e geometry: octahedral |
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3 atom 3 lone pair |
t shape e geometry: octahedral |
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2 atom 4 lone pair |
linear e geometry: octahedral |
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What is the general bonding trends of hard/soft acids and bases |
hard bonds with hard soft bonds with soft |
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What are some characteristics of hard acids and bases? |
They have a high charge/radius ratio. Bonding is more ionic, therefore high difference in electronegativity |
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What are characteristics of soft acids and bases? |
more polarizable, bonding is more covalent polarizability increases as volume electrons occupy increases |
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how to calculate bond order
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Draw lewis structure
count number of bonds count number of bond groups divide |
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What was wrong about the Thompson plum pudding model? WHat was right? |
The positive charge was overestimated in terms of how much volume it occupies positive charge in center of atom with e- outside |
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What is the rhydberg equation? |
1/lamda or E=RZ^2(1/n1^2-1/n2^2) n=principal quantum number z=atomic number(proton) |
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Heisenberg uncertainty principle |
cannot know electrons exact location only the position or the momentum |
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orbital |
actual or potential patterns of electron density that can be represented by a wavefunction |
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What was wrong with Rutherfords model of the atom? what was right? |
Rutherford's model of the atom described a dense, heavy, positively charged nucleus surrounded by negative electrons that balance out the charge of the atom. He also concluded that the atom is mostly made up of empty space. does not say anything abot arrangement of electron e- orbiting positive charge |
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Why is the Bohr model wrong? What was right? |
Bohr proposed that electrons move in well defined circular orbits which they do not created shells and shells reflect energy of e- |
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What is a photon?
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A quantized packet of energy
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What was de Broglie's hypothesis? |
Any moving particle or object has an associated wave |
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What expirement allowed for the discovery of the electrions wave properties? |
electron diffraction, electrons were shot at a crystal solid and the trajectories could only be explained by wave properties
showed that there was a measurable mass that behaved as a wave |
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What is the shrodinger equation? |
psi H= psi E psi H represents all properties associated with an electron |
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what is a wavefunction? |
describes the time and/or position of an electrion the phase |
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What happens when you square a wavefunction? |
It gives you the probability density of where to the electron will be found |
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draw d orbitals |
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Define the Bohr radius |
the most probable difference of an electron in the ground state of a H atom point of the maximu where you are most likely to find e- |
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How do you calculate quantum numbers? |
n=given l=n-1 example s=0,p=1,d=2,f=3 m sub l= s=0 p=+/-1,0 d=+/-2, +/-1, 0 f=+/-3, 2, 1, 0 m sub s= +/- 1/2 |
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what does m sub s describe? |
electron spin |
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Describe the process of shielding. |
outer valence electrons are shielded from the charge of the nucleus by the inner electrons |
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What is the relationship between true nuclear charge and efffective nuclear charge? |
as one increases the other increases but not proportionately |
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What is the trend of ionization energy? |
Ie increases as electrons are more tightly bound to the nucleus which means smaller atoms will have a higher Ie. Size decreases from left to right across the periodic table and from top to bottom. The closer an atom is to an octet the higher the Ie to remove an e-. Half filled shells are more stable than partially filled. |
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What is the trend of electron affinity |
increases from left to right and from bottom to top. Is the energy change when a neutral atom attracts an electron to become a negative ion. Those with the most full shells will have a higher affinity. Noble gases are exceptions because electron gain breaks the octet. |
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What is the trend of electronegativity? |
Electronegativity is how strongly an atom is able to attract a bonding pair of electrons. Increases from left to right and from bottom to top. Again half filled are more stable than partial. |
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What is r^2(R)^2? |
the radial distribution function, the probability to find an electron at a given point on the surface of a sphere. Takes into account the spherical surface |
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What does (R)r^2 represent? |
This is the probability to find an e- at a given point
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What is the recipirical of wavelength? |
Energy |
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How do you calculate how many nodes there are? |
n-1 angular node = l remainder are radial nodes |
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In the Hamiltonian equation what represents PE? KE? |
PE=-Ze^2/r KE=-h^2/2m |
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WHat do Slater's rules predict? |
helps calculate the actual charge felt by electron |
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What happens to shielding of outermost electrons when n is increased? |
electrons are highly shielded |
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What is the trend in screening ability with the periodic table? |
down the table increases screening ability |
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What happens to effective nuclear charge as radius decreases? |
effective nuclear charge increases |
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What happens to radius when an electron is added? |
increases |
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Where is an electron added when discussing electron affinity? |
LUMO |
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Where is electron removed when discussing ionization energy? |
HOMO |
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What is the relationshi between Ie Ea and EN |
EN=Ie+Ea/2 |
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What is polarizability? |
how easility an atom is affected by an external charge small atoms are less polarizable |
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What is equilibriu bond length? Covelent radius? van der waals radius? |
equilibrium=distance between centers of the measured atoms covalent=R=ra+rb van der waals=non bonded atoms |
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Which orbitals are mostly involved in bonding? |
s and p not really d d mainly defines other characteristics |
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What is the isoelectronic principle? |
molecules with the same number of valence electrons have similar properties and geometries pretend you are looking off from central atom and if there are no variances in lone pairs and the valence electrons are equal they are isoelectronic |
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WHat are coordinate compounds? |
metal cations accepting lone pair from lewis bases |
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Which atoms tend to be soft? |
positive transition metals generally Ru-Cd and Os-Tl softer atoms are more easily oxidezed/reduced |
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Why did Pauling introduced EN? |
to explain the extra bond energy of polar molecules |
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What is the equation for bond energy Pauling used? |
E(AB) the heternuclear bond=.5(E(AA)+E(BB)) the covalent bond + 23 (Xa-Xb) the ionic difference. Highlights if bond is more ionic or covalent. |
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What are the numerical scales for the differences in type of bonds |
X>2 ionic 0.5>X>2.0 Polar covalent X<0.5 covalent |
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What does looking at electronegativity differences help with? |
It helps validate and recognize some of the expected reactivities of molecules. The same molecule can behave very differently depending on the electonegativity of the atom it is bonding wiht. |
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When does a pi bond form? |
Only when two p orbitals overlap on the py orientation if it is px overlab it is a sigma bond |
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How does the LCAO-MO deal with atomic orbitals? |
It includes them by acknowledging that molecular orbitals are formed from the mixing of atomic orbitals |
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What is the relationship between nodes and energy? |
More nodes=more energy |
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How are the nonmixing parts of molecules described? |
they are still just described as atomic orbitals becaues they dont involve in bonding or interact at all |
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What is the relationship between molecular and atomic orbitals? |
They are conserved AO=MO |
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What happens when AOs are very different in energy? |
THey dont mix and therefore the bond is not covalent AOs that dont overlap in space dont interact |
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How do you calculate bond order from MO diagrams? |
1/2(Bonding electrons-antibonding electrons) |
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WHat does u stand for? |
ungarad-opposite phase |
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What does g stand for? |
garad- in phase |
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What happens when the difference of energy in a bond is increaseD? |
ionicity of bond is increased |
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What is the overlap intergral? |
The amount that the orbitals overlap when bonding Ranges from 0>S>1 never is 1 more close to 0 |
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What happens to the charge as atoms move closer together? |
The charge begins tostabilize from feeling the positive charge |
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Where does a metal act as a Lewis acid? |
mainly thorugh s orbital HAS to be empty |
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Why are the d orbitals split in metal ligand interaction? |
dxz, dyz and dxy are decreased in energy because they have no symmetry to bond with another typeof orbital dx2 and dxy2 high in energy d orbitals pointing at ligands in cartesian axes are higher in energy |
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What is the relationship between bond strenght and energy? |
stronger the bond stronger the energy |
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How are bond order and length related? |
Inversely proportional |