Busy. Please wait.

show password
Forgot Password?

Don't have an account?  Sign up 

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know (0)
Remaining cards (0)
Know (0)
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

MCAT Chem Packet 1


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


Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then tap the card to flip it. If you knew the answer, tap the green Know box. Otherwise, tap the red Don't know box.

When you've placed seven or more cards in the Don't know box, tap "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just tap on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards