Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
MCAT Chem Packet 1
Chemistry
| Question | Answer |
|---|---|
| Avogadro's # | 6.022X10^23 |
| Mass # | protons+neutrons |
| charge of electron | 1.6x10^-19 Coulombs |
| atomic # Z | # protons=#electrons unless it's charged |
| isotope | #neutrons change so mass changes but atomic #same |
| electron | - charge, closer to nucleus the lower energy level, less interaction w/environment |
| cation | gain + charge, loose e-, decrease radius, move to left of periodic table for e- config |
| anion | gain - charge, increase radius, move to right on periodic table for e- config |
| valence e- | VE=atomic group # |
| Plancks quantum theory | energy is emitted as electromagnetic radiation from matter exist as discrete bundles called quanta E=hf=hc/╗(wavelength) c=3.0X10^8m/s h=6.626x10^-34 J*s |
| Bohr Model | Predicted changes in discrete amounts w/ respect to n L=nh/2π n=principal quantum # h=planck constant |
| Bohr Energy of electron | E=-Rh/n^2=-Rh(1/n^2initial-1/n^2final) E=- absorption E=+ emission E↑ negativity↓ n↑ e- goes from lower level to higher they AHED: Absorb light, Higher potential, Excited, Distant from nucleus |
| Energy of photon emmitted | E=hf=hc/wavelength |
| Lyman Series | Group of H emission lines corresponding to transition from upper levels n>1 to n=1 |
| Balmer Series | From energy levels n>2 to n=2 |
| Paschen Series | From energy levels n>3 to n=3 |
| Absorption | energy bands when energy absorbed. see light emitted NOT absorbed |
| heisenberg Uncertainty Principle | uncertainty of position of a particle and it's momentum. You can know position but not momentum and vice versa ▲x▲p≥h/2 |
| Pauli Exclusion Principle | No two e- in the same atom can have same four quantum #'s |
| Quantum Number Table | #1 principle (n) (1,2,3..) shell (energy level, # of period # on periodic table) #2 azimuthal (l) (0,1..(n-1)) subshell: s L=0; p L=1; d L=2; f L=3 #3 magnetic (ml) (-L to L) orbital: px;py;pz #4 spin (ms) (-1/2, +1/2) spin (↑↓) |
| Quantum number equation | # of total orbitals= n^2 # of e- within shell= 2n^2 # of e- within subshell= 4L +2 |
| Aufbau Principle | each new proton added creates new element and each new e- occupies lowest energy level (n) BOWLOW stability ↑ fill lowest n level with n+l if same pick lowest n |
| Electron configuration | 1) List shells &subshells of element e- from lowest to highest 2) Add subscript after each subshell to indicate # of e- Ex: Fe: 1s2 2s23s23p64s23d6 or [Ar]4s23d6 Exception: Half & completely filled subshell preferred |
| Electron Config Exception | Exception: Half & completely filled subshell preferred Ex: Cr: [Ar]4s23d4→[Ar]4s3d5 Anion: move toward RIGHT of element Cation: move toward LEFT of element Ex: [Br-]: [Ar]4s2 3d10 4p6 |
| Hund's Rule | e- will NOT fill any orbital in the same subshell until all orbitals have at least 1 e- ie: Fill them single than paired (↑↓) |
| Paramagnetic | elements with unpaired e- Ex: Li 1s:↑↓ 2s:↑ & PARALLEL when external field applied |
| Diamagnetic | elements with NO unpaired e- & UNAFFECTED Be: 1s:↑↓ 2s:↑↓ |
| Periodic table trends | Across Periodic Table: ↑ Ionization Energy, Bond Order, Electron Affiinity, Zeff, Electronegativity ↓Atomic radius Down Periodic Table: ↓Ionization Energy, Bond Order, Electron Affiinity, Electronegativity ↑Atomic radius, Zeff |
| Chemical properties of Periodic Table | Metals: Loose hold on outer e-, form cation, thermal &electrical conductive Metalloids: Metal &nonmetal characteristics Nonmetals: Form covalent bonds w/on another, form anion, ↓ melting pt |
| Atomic Radius | Distance from center of nucleus to valence e- ↑radius↓down periodic table→across table (R to L) due to protons weaker pull to e- |
| Electrostatic force | Force b/w charged objects (F=kQ1Q2/r^2); attractive b/w opp charges & repulsive b/w like |
| Effective Nuclear Charge (Zeff) | Amount of charge felt by most recently added e- ↑Zeff←(L to R) ↓Top to bottom ↓shielding |
| Ionization energy | Energy required to detach an e- from atom ↑IE→(L to R)↑Bottom to top Why? e- are closer to nucleus |
| First vs Second IE | First IE: Energy required to detach 1 e- from neutral atom to form (+1) cation Second IE: Energy required to detach 2 e- from neutral atom to form (+2) cation Second IE>First IE b/c second IE more stable |
| Electronegativity | Tendency of atom to attract e- shared in covalent bond The LARGER the diff b/w electronegativities the LARGER the polarity so ↑attraction |
| Electron Affinity | willingness of an atom to accept addition of e- E RELEASED when e- added ↑EAffinity→(L to R)↑Bottom to top table ▲H is (-) & EXOTHERMIC to the right &up periodic table ▲H is (+) & ENDOTHERMIC for noble gases |
| octet rule | atom will bend until it has full outermost shell similar to noble gases Exceptions: some have less than 8e-;in or beyond 3rd period can have more than 8e- so more than 4 bonds |
| Lewis Structure Rules | 1) Find total # of valence e- for all atoms 2)Use pair of e- to form single bonds 3) arrange remaining e- into lone pairs &double or triple bond to satisfy duet/octet rule Total # e-=Σvalence e- |
| Formal charge | VE-(Nnonbonding (dots)+ 1/2Nbonding (sticks)) |
| Bond ranking | Ionic>covalent>hydrogen bonding>dipole-dipole>van der waals |
| Ionic bonding | -covalent bond where valence e- are transferred to one atom (unequal sharing) creating polarity -most enegative atom attracts e- -b/w metal &nonmetal -High melting pt -soluble in H2O & insoluble in nonpolar conducts electricity in aqueous soln |
| Covalent bonding | -valence e- are shared equally -similar enegativities -soluble in nonpolar -insoluble in H2O -low melting pt and boiling pt -nonconductor of heat & electricity |
| Dipole Moment | occur when (+) charge center is not same as (-) charge so e- are pulled to one side |
| Polarity | -determined by geometry of molecule (due to dipole orientation) |
| Intermolecular attraction Types | attraction b/w molecules due to dipole moment 1)London Forces (van der waals) 2) Hydrogen Bond 3) Dipole-dipole 4)Induced dipole 5) Instantaneous dipole moment |
| London Forces | weakest interactions b/w two instantaneous dipoles ↑size of atom/structure↑dispersion forces |
| Hydrogen bond | bond b/w H, N,O,F involved in intra(b/w molecule) & inter(b/w 2 compounds) interactions |
| Dipole-Dipole | occurs b/w oppositely charged ends of polar molecules; stronger than London evident in interactions in solid &liquid phase but negligible in gases |
| Induced Dipole | occurs when dipole moment is created in NON-POLAR molecule or bonded to a polar, ion molecule or electric field -weaker than permanent dipoles |
| Instantaneous Dipole Moment | arise spontaneously in non-polar molecule Why? -e- move around & become uneven create dipole in neighboring atoms |
| Bond Length | distance b/w two nuclei of atoms involved in bond ↑Shared e-↓Bond length |
| Bond Energy (Bond Dissociation Energy | energy required to break bond and separate components to gaseous state ↑Bond E↑Bond Strength↓Bond length |
| Realtionship b/w bond length, strength, &energy | Bond Length: single bond >double bond>triple bond Bond Strength: single<double<triple Bond Energy: single<double<triple |
| Hybridization | sigma bond: bounding pair of e- found in space b/w bonding atoms Lowest Energy; Strongest Most Stable pi bond: overlapping p orbitals, More Reactive ↑s character↓bond length↑bond strength↑bond energy↑stability sp (50:50)>sp2(33:66)>sp3(25:75) |
| Aromaticity &Huckel Rule | 4n+2π=# of e- ↑e- delocalization ↑stability |
| Resonance Structure | Molecule is an average of all resonance structure w/lowest energy & greatest stability ↓separation of charge ↑stability ↓formal charge on most atoms ↑stability conjugate base of an acid exhibits resonance ↑stability so weaker base & stronger acid |
| Fisher Projection | OH H ╪ H H H CH3 Horizontal lines(---): out of scope vertical lines(: into page |
| Newman Projection | Anti: Θ=180 Gauche: Θ=60 Eclipsed Θ=120 Fully Eclipsed Θ=0 |
| Valence Shell Electron Pair Repulsion(VSEPR) Geometry Linear (sp) & Trigonal planar (sp2) | [# of bonds=2] [#lone pairs=0] linear AX2 [#of bonds=3] [#lone pairs=0] trigonalplanar AX3 [#of bonds=2] [#lone pairs=1] bent AX2E1 |
| Valence Shell Electron Pair Repulsion(VSEPR) Geometry Tetrahedral (sp3) | [#bonds=4][#lone pairs=0] tetrahedral AX4 [#bonds=3][#lone pairs=1] trigonal pyramidal AX3E1 [#bonds=2][#lone pairs=2] bent AX2E2 |
| Valence Shell Electron Pair Repulsion(VSEPR) Geometry Trigonal bipyramidal (sp3d) | [#bonds=5][#lone pairs=0] trigonal bipyramidal AX5E0 [#bonds=4][#lone pairs=1] seesaw AX4E1 [#bonds=3][#lone pairs=2] T-shape AX3E2 [#bonds=2][#lone pairs=3] linear AX2E3 |
| Valence Shell Electron Pair Repulsion(VSEPR) Geometry Octahedral (sp3d2) | [#bonds=6][#lone pairs=0] octahedral AX6E0 [#bonds=5][#lone pairs=1] square pyramidal AX5E1 [#bonds=4][#lone pairs=2] square planar AX4E2 [#bonds=3][#lone pairs=3] Tshaped AX3E3 [#bonds=2][#lone pairs=4] linear AX2E4 |
Created by:
aperez48
Popular MCAT sets