Gen Chem Flashcards
What equation do we use to measure the energy absorbed/emitted when an electron shifts energy levels?
E=2.18x10^-18 [(1/nf)-(1/-ni)]
Define the Lyman Series
UV rays and ground state is always n=1
Define the Balmer Series
emittes visible light and final state is n=2
Define the Paschen Series
emitts infrared light and the final state is n=3
How do you determine l (azimuthal quantum number)?
n-1
What are the possible values of ml?
-l to +l
What is the one difference between paramagentic and diamagnetic? Which one repels mag field and which one is attracted to it?
Paramagnetic have unpaired electrons that will orient their spins in alignment with mag field.
Diamagnetic have only paired electrons that will be slightly repelled by a magnetic field
What are 5 characteristics of metals?
- Found on left side and midde of periodic table
- Lustrous: shint solids
- malleability
- ductility: ability to be pulled and drawn into wires
- Conductors: bc valence electrons of metals are loosely held
What are four characteristics of nonmentals?
- Upper right side of periodic table
- brittle in solid state
- show little or no metallic luster
- poor conductors
Where can you find the metaloids on the periodic table?
“staircase” in periodic table
What are 4 characteristics of alkali metals?
- In group 1
- densities are lower than other metals
- oxidation state of +1
- react readily with nonmentals because easily lose one electron
What are the groups of active metals?
Alkali metals (group 1) and Alkaline (group 2) earth metals
What are three characteristics of Chalcogens?
- Group 16
- Six electrons in valence shell
- oxidation state of -2 or +6
What are four characteristics of Transition Metals?
- Group 3-12
- Have many different possible oxidation states because can lose electrons from s and d orbitals. (oxidation states correspond to different colors)
- high melting and boiling points
What three factors determine the length of an element’s atomic radius?
- Zeff
- Number of valence electrons
- The number of electron shells
Which type of group in the periodic table is most likely to form a complex ion in H20?
Transition metals (Ex: form a hydration shell)
What are five atoms that do not form complete octets?
H, He, Li, Be, B
What are the three elements that can have expanded octets?
P, S, Cl (period 3 and greater)
What are five characteristics of ionic bonds?
- high melting amd boiling points due to electrostatic attractions
- solubility in water
- good conductors
- crystal lattice arrangement to minimize repulsive forces
- large electronegativity difference between ions
What is the change in EN in order to form a nonpolar covalent, polar covalent, and ionic bond?
Nonpolar: delta EN: 0-0.5
Polar: 0.5-1.7
Ionic: 1.7 or higher
Define equivlanets and how do you calculate it? Gram equivalent equation?
How many moles of the thing we are interested in will one mole of a given compound produce?
Gram equivalent=Molar Mass/(number of particles of interest produced or consumed per molecule)
Equivalents=(mass of compound)/Gram equivalent weight (g)
What two things happens during a nuetralization rxn?
- double replacement (metathesis rxn) rx with acid and base
- produce a salt
Chemical formula of:
Phosphate
Hypochlorite
Ammonium
Phosphide
Bicarbonate
Nitrite
Chomium (II)
Sulfate
PO4-3
ClO-
NH4+
P-3
HCO3-
NO2-
Cr2+
SO4-2
What is the difference between ite and ate?
smaller amount of oxygen is -ite and greater amount of oxygen is -ate
What are three relatioships defined by the Arrhenius Equation?
- As the frequency factor (how often molecules in a rxn collide) increases, the rate constant increases
- As temperative increases, the rate constant increases
- Increasing activation energy, decreases the rate constant
What is the difference between a homogeneous and a heterogenous catalysis?
- homogeneous: catalyst is in the same phases as the reactants
- heterogenous: catalyst is in a distinct phase
What is one similarity between the transition state theory and the collision theory? One difference?
- One simularity: both require a certain amount of activation enery to overcome
- Differences:
Transition state focuses on that compounds in transition state have the highest energy that can proceed forward or back
Collision theory focuses on the energy and orientation of reactants and each rxn is all or nothing
What are four key ideas a zero-order reaction?
- the rate of formation of products is independent of the changes in concentration of the reactants
- these reactions have constant rate equal to k
rate=k
- change rate by changing temp or adding a catalyst (chaning activation energy)
- [A] vs time curve is linear with a negative slope (slope is -k)
What are three key ideas of first order reactions?
- rate that is directly proportionate to only one reactant
- rate=k[A]1
- [A] vs. time –> nonlinear graph
ln[A] vs time–> linear with negative slope (-k)
What are three key ideas of second-order reactions?
- rate that is proportional to the concentration of the two reactants or the square of one reactant
- rate=k[A]2 or rate=k[A]1[B]2
- [A] vs time graph is exponential and 1/{A] vs time is linear with + slope
What are three ideas for mixed order reactions?
- reactions with rate orders that vary over reaction
- [A] is high at first so rxn will appear to be first order with respect to A
- [A] is low at end so rxn will appear second order with respect to A
What is one equation for Keq?
kf/kr
What are the three difference between kinetic producs and thermodynamic processes?
- Kinetic products are favored at low temps with low heat transfer and thermodyanmic products are favored at high temps with hight heat transfer
- free energy that must be added to the kinetic pathway is lower to reach the transition states than the thermodyanmic pathway so kinetic products form faster
- the free energy of the thermodyanmic products is lower than the kinetic products so thermodyanmic products have greater stability and more negative delta G
What is the difference between specific heat and heat capacity?
- Specific heat: energy required to raise the temp of one gram of a substance by one degree celsius
- Heat Capacity: the product of mass and specific heat and is the energy required to raise any given amount of a substance one degree Celsius
What is one equation to find (delta G0)? Two equations to find delta G?
- Delta G0=-RTlnKequ
- Delta G=Delta G0+RTLnQ
Delta G=Delta H-T(DeltaS)
What is the difference between STP and standard state conditions?
STP is at 273 and Standard state conditions are at 298
STP is used for gas law calculations
What is the equation for density?
p=m/v=(PM)/RT
M=molar mass
m=mass
What are differences between Boyle’s law, Charle’s Law, and Gay-Lussac’s Law?
Boyle’s Law: PV=k or P1V1=P2V2
Charle’s Law: V/T=k or V1/T1=V2/T2
Gay-Lussac’s Law: P/T=k or P1/T1=P2/T2
At STP, what is the volume that one mole of gas occupies?
22.4 L
How do you find the partial pressure of a gas?
PA=PTXA
What are the 5 assumptions of the Kinetic Molecular theory?
- gas molecules have volume that is negligible
- gas molecules have no intermolecular attraction/repulsions
- gast particles are in random, continous motions, with collisions with particles and container
- collisions between two gas molecules are elastic
- Average KE of gas particles is propotional to the absolute temp of the gas
What is Graham’s Law and what are the conditions?
r1/r2=(M2/M2)1/2
under isothermal and isobaric conditions
What is effusion?
flow of gas particles under pressure from one compartment to another through a small opening
What is solvation?
the breaking of intermolecular forces between solute particles and between solvent particles, with intermolecular forces between solvent and solute particles
What are 3 characteristics of complex ions
- are composed of metallic ions bounded to various neutral compounds and anions (ligands)
- formation of complex ions increase solubility of insoluble ions
- coordination covalent bonding
What is chelation?
formation of coordinate bonds
How do you find molality?
moles of solute/kg of solvent
Define normailty?
the number of equivalents of interest per liter of solution. Equivalent is equal to a mole of a species of interest
ex: 1 mole of MNO42- will accept 5 moles of electrons so 1M solution would be 5N
What is the definition of a colligative property?
are those that depedend on the amount of solute present, but not on the actual identity of the solute particles
ex: vapor pressure depression, boiling point elevation, freezing point depression, osmotic pressure
How can you find boiling point elevation and freezing point depression?
deltaT==iKbm
m=molality
i=van’t Hoff factor –> what the compound breaks down into (ex: MgCL2 has a factor of 3)
deltaT==iKfm
Kb is for the solvent
How can you find osmotic pressure?
Π=iMRT
ixM is osmolarity
Define vapor pressure depression?
presence of other solutes decreases the evaporation rate of a solvent without affecting its condensation rate, decrease vapor pressure. Depression in vapor pressure also increase boiling point
what does Raoult’s law state?
ideal solution behavior is observed when solute-solute, solvent-solvent, and solute-solvent interactions are all very similar
Do you need energy or release energy to break bonds?
need energy (endothermic)
What does it mean to have a posisitve deviation from Raoult’s law?
higher vapor pressure than predicited because have stronger solvent-solvent, solute-solute interactions. Therefore particles do not want to stay in solution and will evaporate, creating a high vapor pressure
What is the differene between Arrhenius, Bronsted-Lowry, and Lewis Bases/Acids?
Arrhenius: acids dissociate to form H+ and bases dissociate to form OH-
Bronsted-Lowry: Acids are H+ donor and Bases are H+ acceptors
Lewis: Acids are e- pair acceptors and bases are e- pair donors
What is the buffering region in a titration?
This is the flattest protion of the titration curve so it is resistant to changes in pH
What is the half-equivalence point in a titration curve?
[HA]=[A-]
What is the equivalence point in a titration curve?
it is the steepest point in the curve and occurs when all acids equals the amount of base added. All acid has been converted into base
NiVi=NfVf
What is the end point of a titration curve?
the point at which the indicator changes to its final color
What is a polyvalent acid and base?How to find normaility?
can donate or accept multiple electrons. Normaility of a solution with a polyvalent species is the molarity of it times the number of protons it can donate or accept
How do you find the gram equivalent weight of an acid?
It is the weight that releases 1 acid or base equivalent from a compound. Ex: If contains 3 protons, find gram equivalent weight by dividing the mass of one mole by three
What are the two products of a combustion rxn?
CO2 and water
What is a Disproportionation rxn?
types of redox reaction in which an element undergoes both oxidation and reduction in producting its products
What is a complete ionic equation? What is a net ionic equation?
- accounts for only the ions present in rxn (split compounds into ions
- get rid of spectator ions, appear on both sides of equation and do not participate in rxn
What is an oxidation-reduction titration?
follow tranfer of charge and inidicators change color when certain voltages of solutions are achieved
What are three traits of a Daniell Cell?
- Anode: oxidation of Zn
- cathod: reduction of Cu2+
- need a salt bridge
What is the electrodeposition equation?
helps determine the number of moles of element being desposited on plate
mole M=(It)/nF
F=96,500
What is one type of recharagable battery?
Lead-acid battery
How do you find Gibbs free energy using Ecell?
delta G0=-nFEcell0
What is the nernst equation?
How to find the standard electromotive force of cell?
E0cell=E0red,cathod-E0red,anode
If the surface area of an electrod is increased, what does it affect?
more electrons, so more current
What is hydrosulfric acid?
H2S
When looking for entropy changes, what should you look for?
changes in phases
Will the addition of an innert gas alter equilibrium?
No
What influence reactivity in water?
it is based on ionization energy (lower IE, tend to lose e easily, allowing them to form oxides in water)
What is thermal equalibrium?
q1=q2
What is the heat capacitance equation?
q=mC(delta T)
How do you find the isoelectric point?
pI=(1/2)(pKa1+pKa2)
What is the Pauli exclusion principle?
when electrons have same spin
What happens to the boiling point when you add a solute?
increase BP, because the rate at which water molecules can break through the liquid surface decrease, more KE to produce Pvap=Patm
What happens to Kw when you increase temp?
Kw increases, so pKw decreases and both pH and POH will get smaller
How do you calculate effective nuclear charge?
protons-# of shielding e- in non valence shells
What is the heisenberg uncertainty principle equation?
delta x (delta p) > h/(4pi)
When does the ionization energy have a drastic increase?
after noble gas configuration
what the order of removal?
highest n. (p–> s–> d)
What does the magnetic quantum mean?
distinguishes the shells and describes the orientation in space (m)
What does the principle quantum number distinguish?
determines the size and energy level
What does the angular momentum distinguish?
determines the shape
If two gas samples are that the same temp, will the average KE of the molecules be the same in each sample? Total KE?
yes, but no total kinetic energy bc depends on number of moles of gas
How can you relate pressure to n?
P1/n1
How can you calculate rate of effusion?
(molar mass)^(1/2)
Are gases more soluble in liquids at higher or lower temps?
lower temps
How do you find the pH of a weak acid?
ka=[H30+][A-]/[HA]
What does a large Ksp mean?
high solubility
Do all salts containing Na dissolve?
yes
How do impurities impact melting points?
lower it and make it more broad
What does eluting strength mean?
depends on how strongly a compounds absorbs into stationary phase. More polar in TLC will have a high eluting strength and stick to stationary phase because more polar
How does the number of dissolved components effect boiling point?
Delta T=Kbnm
increase, increase BP
(molality)
Ho many pi electrons in double bond?
2
How many electrons involved in lead acid batery?
2
what is one mole of electrons equal to?
6 x10^23 electrons/mole
What types of molecules can absorb IR radiation? Which ones cannot?
Only molecules that undergo a net change in dipole moment during rotational and vibrational motion can absorb IR radiation. Diatomic molecules do not return IR radiation
What is mi?ms?
mi: magnetic number/spatial orientation
ms: spin orientation
What is ozonolysis?
cleavage of alkene/alkynes with ozone (O3)
C-C bond will be replaced by a C=O
What are three weak bases?
enamines (C=C-NH2), imines N=R, amines
How do you find the % of R and S?
+125.6 R–> -125.6 R
(125.6)(x)+(-125.6)(1-x)=mixture
How do you find the pI for basic and acidic substances?
- if basic, take the two highests pI average
- for acids, take the two lowest
What does 1L equal in cm3?
103
In an isolated system, when is entropy maximized? When is entropy minimized?
when no energy gradient, so when system is in equilibrium and system is unable to perform work
mimized when there is a gradient bc then there is concentration of energy
What are two things that increases entropy?
Entropy increases when the solubility of a gas decreases and it escapes from a solvent.
Entropy generally increases as molecular complexity increases (KOH vs. Ca(OH)2) due to the increased movement of electrons.
What is the 3rd law of thermodynamics?
calculate absolute entropy
When do gases behave ideally?
low pressure, high temp
What geometry is one lone pair and three atoms attached to central atom?
trigonal pyramidal
Can hydrogen sulfide undergo H-bonding?
No, only, N, O, F
How can you tell when atoms are not sp3 hybridyzed?
do not participate in pi bonding and cannot delocalize lone pairs into pi system
How do the geometry of sulfer dioxide and carbon dioxide differ?
CO2 is linear and SO2 is bent
Which cell cycle check point is the restriction point, or point where the cells are committed to mitosis?
G1 and G2 serves to pause to check for impurfections
What are:
Boyle’s Law
Charles’ Law
Gay-Lussac’s Law
Avogadro’s Law
- Boyle’s Law” PV=PV
- Charles’: V/T=V/T
- P/T=P/T
- n/V=n/V
Why does being at high sea level cause alkolosis?
because reducing O2 so breath more, but decrease CO2. As a result, need to restore equilibrium so will shift equilibrium to the right to produce CO2 but will lose H+ in blood
What function causes a trend of first order kinetics to be linear and slope downward?
Ln[M] vs time
How do you find the Keq of sum fo rxn?
multiply all of them. do not forget Ksp because the formation of the solid if just the reciprocal
What can you be certain about this rxn?
exergonic, not exothermic bc do not know if release excess energy as heat
In the mobil gas phase of gas chromatagraph, what is one requirment of the gas?
it must be inert
For a monoprotic acid, do you have to multiple the concentration do get the normality?
no
When will a substance ppt?
Q>Ksp
How do you find Kb?
10-14/Ka
Does increase complexity of compound/dissolve in solvent increase or decrease entropy?
increase
are ionic bonds easier or hard to break?
easier
If polar molecules mix well with water, what happens to entropy?
it increases, more disorder
What are two conditions when gas have greater solubility in liquid?
Cooler temps, increase in partial pressure of gas
How can you find deltaG using Keq?
Delta D=-RT ln(Keq)
What might give a substance an intense color?
delocalization of electrons
Why is liquid water deleted from the equilibria equation?
because the solvent amount stays the same
What is the difference between the critical point and triple point?
Critical point: need very high temp and pressure
triple point: abelt to interconvert the samples between three phases with minimal change in pressure and temp
How do you find freezing point depression?
Delta Tf=kfmi
m=molality
i=number of dissolved particles
When does a titration act as a buffer?
with weak acid and weak base titration at half equivalence
How do enzymes affect chemical rxn?
stabilize the transition states and decrease activation energy
What is hunds rule?
fill orbital with one electron first with same spin
What is pauli exclusion?
electrons have opposite spins in each orbital
What is heat of fusion?
energy for melting
What does the volume of a gas change more than liquid when you change temperature?
Gases are more compressible than liquids
Does Doppler effect impact sound?
no, it does not impact intensity, only impacts freq
Does freq change when changing medium?
no
What radiaactive particle is most penatrative?
gamma photons
Are salts hydrophilic or hydrophobic?
hydrophilic
Define pKa?
is the pH where exactly half of the compound in the solution is in the protonated form and half is in the deprotonated form
What two factors can change K?
pH and temp
Inert?
resistant to change
what happens if an amino acid stops moving on electrophoresis gel?
have reached its pI and has no charge
Are zeroth order rxns impacted by concentration and temp?
no
What is a compound?
2 or more unique elements
Are d orbital paramagnetic or diamagnetic?
paramagnetic
How does increasing temp change pH?
dissociation of H+ and OH is endothermic so increase temp will increase dissociations so pH and pOH will decrease and Kw will decrease
What type of acid is HClO2
weak
How do volatile compounds impact BP?
lower vapor pressure of solution
What is bicarbonate and carbonate?
bicarbonate: HCO3-
carbonate: CO32-
What color will blue litmus paper turn in acidic conditions?
red
