Search found 100 matches
- Tue Mar 10, 2020 9:35 pm
- Forum: First Order Reactions
- Topic: Equilibrium constant and elementary reaction rate constants
- Replies: 5
- Views: 1322
Re: Equilibrium constant and elementary reaction rate constants
K=(k'/k) is the relationship between equilibrium constant and rate constants
- Tue Mar 10, 2020 9:34 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Chemical Equilibrium biological examples
- Replies: 2
- Views: 307
Re: Chemical Equilibrium biological examples
An example is a neuron and its action potential. It is at equilibrium, but when it receives a signal, Na+ ions rush in causing it to veer from equilibrium until the K+ ions rush out, returning it to equilibrium.
- Tue Mar 10, 2020 9:32 pm
- Forum: *Enzyme Kinetics
- Topic: Poison a Catalyst
- Replies: 3
- Views: 306
Re: Poison a Catalyst
It may matter conceptually, but I doubt quantitatively. Poisoning a catalyst is to cause it to lose its function.
- Tue Mar 10, 2020 9:31 pm
- Forum: *Enzyme Kinetics
- Topic: Collision model
- Replies: 2
- Views: 266
Re: Collision model
It helps us determine which collisions occur with enough energy to overcome the activation energy. This helps us determine A in the Arrhenius equation
- Tue Mar 10, 2020 9:30 pm
- Forum: Phase Changes & Related Calculations
- Topic: Heating Curve
- Replies: 2
- Views: 306
Re: Heating Curve
probably not. the calculations should be sufficient
- Mon Mar 02, 2020 6:10 pm
- Forum: General Rate Laws
- Topic: Order
- Replies: 5
- Views: 537
Re: Order
you look at the graph and compare it with the 3 possible orders to determine which one best fits the graph shown
- Mon Mar 02, 2020 6:08 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Units for lnQ
- Replies: 2
- Views: 290
Re: Units for lnQ
Q is a ratio so it has no units because they cancel out
- Mon Mar 02, 2020 6:07 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: instantaneous rate
- Replies: 16
- Views: 989
Re: instantaneous rate
It is more precise for that specific moment in time
- Mon Mar 02, 2020 6:07 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cell Diagram for 6L.5(b)
- Replies: 2
- Views: 189
Re: Cell Diagram for 6L.5(b)
the TA's have said that the book writes it in different format sometimes but that we should stick to what we were taught in lecture and we'll be ok
- Mon Mar 02, 2020 6:06 pm
- Forum: Balancing Redox Reactions
- Topic: Electrochemical series.
- Replies: 4
- Views: 381
Re: Electrochemical series.
It is a list of reduction half reactions
- Mon Feb 24, 2020 12:04 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Platinum
- Replies: 5
- Views: 394
Re: Platinum
It's a common electrode because it is inert and doesn't interfere with the redox reaction
- Mon Feb 24, 2020 12:04 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Salt bridge
- Replies: 6
- Views: 453
Re: Salt bridge
It keeps the 2 solutions neutral so electrons can continue transferring
- Mon Feb 24, 2020 12:03 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidizing/Reducing Agent
- Replies: 8
- Views: 620
Re: Oxidizing/Reducing Agent
the oxidizing agent gains electrons and the reducing agent loses electrons
- Mon Feb 24, 2020 12:03 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Usage for Nernst equation
- Replies: 7
- Views: 665
Re: Usage for Nernst equation
it is used to find the nonstandard cell potential
- Mon Feb 24, 2020 12:02 pm
- Forum: Balancing Redox Reactions
- Topic: Platinum in cell diagram
- Replies: 10
- Views: 797
Re: Platinum in cell diagram
You need a metal to conduct the electrons and platinum is inert and doesn't interfere with the redox reaction
- Tue Feb 18, 2020 8:58 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Test #2
- Replies: 4
- Views: 457
Re: Test #2
It will probably include Gibbs free energy and all the material that we get through this week (electrochemistry)
- Tue Feb 18, 2020 8:57 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: 5J.15
- Replies: 4
- Views: 258
Re: 5J.15
My book also says 150 degrees celsius which matches up with the 423 K
- Tue Feb 18, 2020 8:56 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: converting T to kelvin
- Replies: 46
- Views: 3756
Re: converting T to kelvin
when talking about delta T then yes it is ok because they are the same in that respect. However, when doing calculations with T you should convert to K because most R values are given with K as the unit
- Tue Feb 18, 2020 8:55 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Constant R
- Replies: 15
- Views: 1103
Re: Constant R
Just look at the units needed in the problem and choose the R with those units same units
- Tue Feb 18, 2020 8:53 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: UA's
- Replies: 3
- Views: 348
Re: UA's
I have found the UA sessions to be very helpful so to anyone who is struggling go to as many as you can!
- Tue Feb 11, 2020 1:14 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Questions about Equation Sheet
- Replies: 3
- Views: 295
Re: Questions about Equation Sheet
Cp = 5/2R and Cv = 3/2R both apply to monoatomic gases. Cp is for constant pressure and Cv is for constant volume
- Tue Feb 11, 2020 1:10 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Internal energy of ideal gas
- Replies: 6
- Views: 531
Re: Internal energy of ideal gas
the change in internal energy is 0 at constant temperature, however the internal energy itself is not necessarily 0 at constant temperature
- Tue Feb 11, 2020 1:08 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Change in entropy of an irreversible process.
- Replies: 3
- Views: 258
Re: Change in entropy of an irreversible process.
delta S of the surroundings does equal 0 because it is free expansion, but delta S total must still increase so that only leaves delta S of the system to contribute to this. Thus, delta S total = delta S system =/= 0
- Tue Feb 11, 2020 1:01 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: 4.17
- Replies: 1
- Views: 150
4.17
4.17 A technician carries out the reaction 2 SO2(g) 1 O2(g) S 2 SO3(g) at 25 8C and 1.00 atm in a cylinder fitted with a piston and maintained at constant pressure. Initially, 0.030 mol SO2 and 0.030 mol O2 are present in the cylinder. The technician then adds a catalyst to initiate the reaction. (a...
- Sun Feb 09, 2020 9:45 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: 4F13
- Replies: 3
- Views: 250
4F13
4F.13 Use data in Table 4C.1 or Appendix 2A to calculate the entropy change for (a) the freezing of 1.00 mol H2O(l) at 0.00 8C; (b) the vaporization of 50.0 g of ethanol, C2H5OH, at 351.5 K.
How would you solve this?
How would you solve this?
- Mon Feb 03, 2020 7:59 pm
- Forum: Calculating Work of Expansion
- Topic: Intergral
- Replies: 6
- Views: 399
Re: Intergral
we won't actually have to do this
- Mon Feb 03, 2020 7:58 pm
- Forum: Calculating Work of Expansion
- Topic: Calculus on The Midterm
- Replies: 8
- Views: 484
Re: Calculus on The Midterm
the only calculus so far is w=integral(PdV)
- Mon Feb 03, 2020 7:57 pm
- Forum: Calculating Work of Expansion
- Topic: Work done by an ideal gas at isothermal, reversibile expansion
- Replies: 3
- Views: 284
Re: Work done by an ideal gas at isothermal, reversibile expansion
the equation for an isothermal, reversible expansion is w=-nRTln(V2/V1)
- Mon Feb 03, 2020 7:56 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Closed Systems
- Replies: 14
- Views: 969
Re: Closed Systems
deltaU = q + w so you can change it by adding heat or doing work
- Mon Feb 03, 2020 7:54 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Combustion
- Replies: 5
- Views: 235
Re: Combustion
at 25 degrees celsius, water is a liquid, so I would assume you use the liquid form.
- Mon Jan 27, 2020 8:50 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Fall Quarter Final?
- Replies: 12
- Views: 858
Re: Fall Quarter Final?
They're still available throughout the quarter I have been told
- Mon Jan 27, 2020 8:50 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Calorimeter
- Replies: 7
- Views: 533
Re: Calorimeter
A calorimeter is used to measure heat of a rxn
- Mon Jan 27, 2020 8:49 pm
- Forum: Administrative Questions and Class Announcements
- Topic: final exam
- Replies: 6
- Views: 388
Re: final exam
you can still pick them up week 4 so don't worry
- Mon Jan 27, 2020 8:48 pm
- Forum: Phase Changes & Related Calculations
- Topic: Enthalpy of sublimation?
- Replies: 8
- Views: 1507
Re: Enthalpy of sublimation?
the enthalpy of sublimation is the sum of the enthalpy of vaporization and fusion
- Mon Jan 27, 2020 8:48 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Stirrer in Calorimeter?
- Replies: 3
- Views: 431
Re: Stirrer in Calorimeter?
It helps mix together the solvent and solute so the rxn can go to completion
- Thu Jan 23, 2020 4:08 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Approximation
- Replies: 5
- Views: 166
Re: Approximation
If K < 10^-3 then you are able to approximate.
- Thu Jan 23, 2020 4:08 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Calculating Kp
- Replies: 6
- Views: 289
Re: Calculating Kp
You can calculate Kp from Kc by using Pv=nRT if given concentrations and enough info. ICE tables are also used for partial pressures as well, though.
- Thu Jan 23, 2020 4:07 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Endothermic Reaction.
- Replies: 7
- Views: 309
Re: Endothermic Reaction.
If delta H is positive, then it is endothermic
- Thu Jan 23, 2020 4:06 pm
- Forum: Phase Changes & Related Calculations
- Topic: Order to Read Book
- Replies: 3
- Views: 106
Re: Order to Read Book
Just follow what he tells us to read on the syllabus.
- Thu Jan 23, 2020 4:05 pm
- Forum: Phase Changes & Related Calculations
- Topic: Steam vs liquid
- Replies: 7
- Views: 366
Re: Steam vs liquid
Steam has more heat energy due to the fact that that energy was inputted in order to vaporize the H2O.
- Tue Jan 14, 2020 1:58 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: ICE charts on tests/exams
- Replies: 8
- Views: 282
Re: ICE charts on tests/exams
I would say yes because partial credit is huge on Lavelle's tests so you should write it out just in case.
- Tue Jan 14, 2020 1:57 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Why Ignore Liquid or Solid Volume When Calculating K
- Replies: 7
- Views: 284
Re: Why Ignore Liquid or Solid Volume When Calculating K
Liquids and solids cannot be dissolved or have their pressures changed in solution so they are not factored in when calculating K.
- Tue Jan 14, 2020 1:56 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Strong Acids/Bases
- Replies: 4
- Views: 159
Re: Strong Acids/Bases
Strong acids and bases completely dissociate in solution while weak acids and bases only partially dissociate.
- Tue Jan 14, 2020 1:56 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Change on Same Side
- Replies: 6
- Views: 250
Re: Change on Same Side
If you increase N2, then H2 will decrease because the reaction will move toward the right.
- Tue Jan 14, 2020 1:55 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: 5I.13
- Replies: 3
- Views: 126
Re: 5I.13
The closer K is to 1, the more stable the reaction is because then the conc of reactants and products is almost equal and neither is favored
- Sun Jan 12, 2020 8:10 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Thinking point 5J
- Replies: 4
- Views: 141
Re: Thinking point 5J
It would have no effect because solids are not part of the equation
- Sun Jan 12, 2020 8:10 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Kp
- Replies: 6
- Views: 429
Re: Kp
K is the general equilibrium constant while Kp refers to the equilibrium constant when using partial pressures.
- Sun Jan 12, 2020 8:08 pm
- Forum: Ideal Gases
- Topic: Ideal gases equation
- Replies: 3
- Views: 261
Re: Ideal gases equation
number of moles
- Sun Jan 12, 2020 8:08 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Different types of K
- Replies: 9
- Views: 304
Re: Different types of K
K is the general equilibrium constant while Kc specifically refers to the equilibrium constant of molar concentrations
- Sun Jan 12, 2020 8:06 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Studying tips
- Replies: 10
- Views: 511
Re: Studying tips
Do every hw problem on the syllabus
- Tue Dec 03, 2019 11:19 am
- Forum: Properties & Structures of Inorganic & Organic Bases
- Topic: Stronger Acid 6C.21
- Replies: 3
- Views: 249
Re: Stronger Acid 6C.21
acetic acid has a less stable conjugate base so it is a weaker acid.
- Tue Dec 03, 2019 11:18 am
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: TEST 2 POLAR molecule
- Replies: 6
- Views: 455
Re: TEST 2 POLAR molecule
It is a tetrahedral molecule, so the dipoles only cancel out when all 4 atoms are the same.
- Tue Dec 03, 2019 11:10 am
- Forum: Amphoteric Compounds
- Topic: water
- Replies: 4
- Views: 408
Re: water
It depends what it is reacting with. In an acidic solution, it acts as a base and vice versa
- Tue Dec 03, 2019 11:08 am
- Forum: Amphoteric Compounds
- Topic: Amphoteric/acidic/basic
- Replies: 5
- Views: 450
Re: Amphoteric/acidic/basic
You need to check what is bonded to the oxygen. If it is a metal, then it is basic. If it is a nonmetal, it is acidic. The metalloids can form amphoteric oxides.
- Tue Dec 03, 2019 11:06 am
- Forum: Octet Exceptions
- Topic: 2.27
- Replies: 7
- Views: 706
Re: 2.27
Radicals only exist when there are an odd number of valence electrons. None of these examples have an odd number so none are radicals
- Tue Nov 26, 2019 4:16 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Oxidation Number vs. Coordination Number
- Replies: 8
- Views: 1413
Re: Oxidation Number vs. Coordination Number
oxidation number is the charge of the central transition metal ion. Coordination number is the number of bonds the central ion forms in the compound
- Tue Nov 26, 2019 4:14 pm
- Forum: Naming
- Topic: Polydentate
- Replies: 4
- Views: 200
Re: Polydentate
There are 3 nitrogen atoms in that molecule so it can bind on the central ion at 3 binding sites. Thus, it is tridentate
- Tue Nov 26, 2019 4:12 pm
- Forum: Conjugate Acids & Bases
- Topic: Acids and Bases
- Replies: 10
- Views: 579
Re: Acids and Bases
Technically all reactions should have equilibrium arrows. However, for strong acids and bases, the reverse arrow is so small that it is omitted
- Tue Nov 26, 2019 4:11 pm
- Forum: Naming
- Topic: polydentate?
- Replies: 7
- Views: 484
Re: polydentate?
polydentate refers to a ligand that binds to the central ion at more than one binding site.
- Tue Nov 26, 2019 4:07 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Complexes
- Replies: 2
- Views: 225
Re: Complexes
Those are the 3 most common shapes that coordinate compounds will take.
- Tue Nov 19, 2019 12:59 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Square Planar Shape
- Replies: 2
- Views: 201
Re: Square Planar Shape
Because there are lone pairs on both sides, the effect of both is equal and opposite so the bond angles are just 90 and 180
- Tue Nov 19, 2019 12:57 pm
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: Types of forces
- Replies: 4
- Views: 207
Re: Types of forces
The question only asks about interactions between SO2 and other SO2 molecules. Thus ion-dipole and dipole-induced dipole interactions do not occur.
- Tue Nov 19, 2019 12:51 pm
- Forum: Dipole Moments
- Topic: Elongated vs. Spherical Molecules
- Replies: 3
- Views: 293
Re: Elongated vs. Spherical Molecules
The best way is to look at the structure
- Tue Nov 19, 2019 12:51 pm
- Forum: Dipole Moments
- Topic: Polar/Nonpolar Molecule Question
- Replies: 2
- Views: 191
Re: Polar/Nonpolar Molecule Question
It is polar because it has a bent shape, thus there is a net dipole toward the O atom
- Tue Nov 19, 2019 12:48 pm
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: interaction potential energy
- Replies: 2
- Views: 192
Re: interaction potential energy
It is always negative because these interactions are attractive. Ep increases with polarizability and decreases as distance increases.
- Mon Nov 11, 2019 3:43 pm
- Forum: Dipole Moments
- Topic: Dipoles
- Replies: 3
- Views: 142
Re: Dipoles
Dipole moments occur in molecules whose atoms have a high enough difference in electronegativity to create partial positive/negative charges.
- Mon Nov 11, 2019 3:42 pm
- Forum: Dipole Moments
- Topic: Dissociation Energies
- Replies: 3
- Views: 163
Re: Dissociation Energies
Breaking bonds always requires energy while forming bonds releases energy
- Mon Nov 11, 2019 3:40 pm
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: Test 2
- Replies: 6
- Views: 258
Re: Test 2
Test 2 is starting Tuesday, Nov 19 in discussion sections
- Mon Nov 11, 2019 3:38 pm
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: london forces
- Replies: 6
- Views: 304
Re: london forces
Electrons are constantly moving throughout an atom so the random dispersion of these electrons leads to London forces forming between atoms and molecules.
- Mon Nov 11, 2019 3:37 pm
- Forum: Dipole Moments
- Topic: Ep Meaning
- Replies: 4
- Views: 522
Re: Ep Meaning
Ep often stands for energy of photon when doing photoelectric problems and for potential energy when in the context of IMFs
- Tue Nov 05, 2019 10:37 am
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Heisenberg Uncertainty Module Question
- Replies: 2
- Views: 142
Re: Heisenberg Uncertainty Module Question
You use Heisenberg's Uncertainty Principle which states m(delta v)(delta x) > h/(4pi). Use this to solve for delta v with what you know.
- Tue Nov 05, 2019 10:35 am
- Forum: Resonance Structures
- Topic: Drawing Resonance Structures on Test?
- Replies: 4
- Views: 237
Re: Drawing Resonance Structures on Test?
The charge goes toward the more electronegative atom.
- Tue Nov 05, 2019 10:29 am
- Forum: Lewis Structures
- Topic: 2D13
- Replies: 4
- Views: 303
Re: 2D13
It wouldn't. SO3 would be most stable with 3 double bonds
- Tue Nov 05, 2019 10:17 am
- Forum: Lewis Structures
- Topic: 2C.3 Question
- Replies: 2
- Views: 169
Re: 2C.3 Question
I'm not totally sure, but on the first outline it does say naming is a skill we should be able to do.
- Tue Nov 05, 2019 10:15 am
- Forum: Lewis Structures
- Topic: 2B 19 a)
- Replies: 1
- Views: 104
Re: 2B 19 a)
For a) the O must have the +1 charge because this is the only way both the N and the O can have a full octet. If the N had the +1 charge it would only have 6 valence electrons, not 8.
For c) the same thing applies.
For c) the same thing applies.
- Mon Oct 28, 2019 2:01 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Atomic spectra post assessment question 42
- Replies: 2
- Views: 140
Re: Atomic spectra post assessment question 42
The above formula is correct and when I calculated it out I got n=6 as my answer. Maybe you just entered it into your calculator wrong
- Mon Oct 28, 2019 1:56 pm
- Forum: Resonance Structures
- Topic: Resonance Hybrid
- Replies: 3
- Views: 119
Re: Resonance Hybrid
resonance hybrids are all the different ways to draw a molecule that has resonance.
- Mon Oct 28, 2019 1:53 pm
- Forum: Ionic & Covalent Bonds
- Topic: valence electrons
- Replies: 6
- Views: 364
Re: valence electrons
manganese has an electron configuration of [Ar] 3d5 4s2 so the electrons in the outermost shell are the 4s2 electrons. This means manganese has 2 valence electrons.
- Mon Oct 28, 2019 1:50 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: 1E #13
- Replies: 3
- Views: 331
Re: 1E #13
Dr. Lavelle mentioned this in class, but basically tungsten is an exception to the exception.
- Mon Oct 28, 2019 1:48 pm
- Forum: Ionic & Covalent Bonds
- Topic: Delocalized Bond
- Replies: 4
- Views: 139
Re: Delocalized Bond
Delocalized bonds are bonds that appear in some resonance forms. Basically, it describes the fact that some electrons are not specific to a particular bond or atom. This is due to resonance and is experimentally proven by the fact that all bonds in a molecule with resonance have a length somewhere b...
- Tue Oct 22, 2019 10:38 am
- Forum: Properties of Light
- Topic: Homework due Next Week
- Replies: 9
- Views: 373
Re: Homework due Next Week
The homework for this week just needs to be any 5 different questions from the quantum world sections
- Tue Oct 22, 2019 10:37 am
- Forum: Quantum Numbers and The H-Atom
- Topic: orientation of orbitals
- Replies: 4
- Views: 739
Re: orientation of orbitals
In the p-subshell x, y, and z are used to refer to the 3 different orbitals that exist in this sub shell. Each is oriented along one of the axes, thus they are labeled px, py, pz.
- Tue Oct 22, 2019 10:34 am
- Forum: Quantum Numbers and The H-Atom
- Topic: Possible Quantum Number Values
- Replies: 4
- Views: 308
Re: Possible Quantum Number Values
There are orbitals past f, such as the g orbital for example. However, this orbital is very unstable. For this class, we only need to know how to use the s, p, and d orbitals and know of the f orbital.
- Tue Oct 22, 2019 10:31 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Ground state electron configuration of ions
- Replies: 4
- Views: 271
Re: Ground state electron configuration of ions
the ground state of an ion or atom simply refers to the lowest energy state of said ion or atom.
- Tue Oct 22, 2019 10:29 am
- Forum: Properties of Light
- Topic: Video module test Question-ATOMIC SPECTRA
- Replies: 1
- Views: 110
Re: Video module test Question-ATOMIC SPECTRA
you must first find the wavelength of krypton-86 radiation. To do this, divide 1 meter by 1650763.73 to find the length of the wavelength. This gives you a wavelength of 6.06x10^-7 or 606 nm. This is visible light. To find the energy we must use E=hv=(hc)/(lambda)=3.28x10^-19
- Tue Oct 15, 2019 5:09 pm
- Forum: Photoelectric Effect
- Topic: Photoelectric effect
- Replies: 5
- Views: 222
Re: Photoelectric effect
Each metal has a specific work function so for all the problems that we will need to know it we will be given it.
- Tue Oct 15, 2019 5:07 pm
- Forum: DeBroglie Equation
- Topic: symbol
- Replies: 4
- Views: 159
Re: symbol
it means proportional to
- Tue Oct 15, 2019 5:05 pm
- Forum: Properties of Light
- Topic: Speed of radiation
- Replies: 3
- Views: 190
Re: Speed of radiation
EM radiation doesn't change speed. Light always travels at 3.0x10^8. This is why the equation c=(lambda)v is viable.
- Tue Oct 15, 2019 4:58 pm
- Forum: Properties of Light
- Topic: Need help with 1A.13 homework problem?
- Replies: 1
- Views: 91
Re: Need help with 1A.13 homework problem?
you use the Rydberg formula with the Constant as 3.29x10^15 because that gives you frequency. After finding the frequency, plug it into c=(lambda)v to find lambda=486 nm. From that, you can check in the table and see it is in the Balmer series and 486 nm is at the higher end of visible light so it i...
- Tue Oct 15, 2019 4:54 pm
- Forum: Properties of Light
- Topic: HW Question 1A.15
- Replies: 2
- Views: 123
Re: HW Question 1A.15
To find n2 you need to use Rydberg's Formula. First you must find frequency using v=c/lambda with lambda=102.6 nm given. Then use Rydberg's formula and solve for n2
- Wed Oct 09, 2019 4:43 pm
- Forum: Properties of Light
- Topic: Speed of Light constant
- Replies: 7
- Views: 326
Re: Speed of Light constant
When he introduced the speed of light in class he used 3.00x10^8 m/s so I think that's what we should use.
- Wed Oct 09, 2019 4:42 pm
- Forum: Photoelectric Effect
- Topic: Photon [ENDORSED]
- Replies: 6
- Views: 322
Re: Photon [ENDORSED]
Photons don't necessarily have "size" as we think about it on a macroscopic scale. They are just packets of energy.
- Wed Oct 09, 2019 4:34 pm
- Forum: Limiting Reactant Calculations
- Topic: Need help on question M.9 for chem 14a
- Replies: 6
- Views: 5288
Re: Need help on question M.9 for chem 14a
To determine if an ion is a spectator ion you just need to look at the product that is stated in the problem. In this problem the product is copper(ii) hydroxide so you know that the sodium and nitrate are the spectators. Because they are spectators, they don't need to be balanced because they exist...
- Wed Oct 09, 2019 2:55 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Positive/ Negative regarding E
- Replies: 3
- Views: 236
Re: Positive/ Negative regarding E
By using E=hv we are finding the frequency of the photon, so we need to worry about the sign of the photon's energy, not the electron's. Because the electron is emitting energy, its sign is negative and so the energy of the photon must be opposite this (positive).
- Wed Oct 09, 2019 2:43 pm
- Forum: Properties of Light
- Topic: Classical Mechanics
- Replies: 4
- Views: 225
Re: Classical Mechanics
light has wavelike properties on a macro scale
- Mon Sep 30, 2019 10:20 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Avogadro's Number
- Replies: 4
- Views: 284
Re: Avogadro's Number
I'm guessing we should go with what professor Lavelle says and follow his lead in using 6.022 instead of 6.0221. Although, I doubt it's significant enough that it will make much of a difference.
- Mon Sep 30, 2019 10:18 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Homework Problem G.17
- Replies: 4
- Views: 349
Re: Homework Problem G.17
It doesn't matter that they are different substances because the units of each are still in moles. So you need to take into account the molar mass of CuSO4.5H2O instead of just CuSO4.
- Mon Sep 30, 2019 10:14 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Formula Units
- Replies: 4
- Views: 176
Re: Formula Units
"Formula Units" and "Molecules" are basically the same thing. The only difference is that formula units refer to ionic compounds while molecules refer to covalently bonded elements.
- Mon Sep 30, 2019 10:12 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Understanding Titrations
- Replies: 3
- Views: 166
Re: Understanding Titrations
Titration is the process of slowly adding one solution of a known concentration into another solution with a known volume. So basically any of the homework problems that we have completed in fundamentals L is an example of titration.
- Mon Sep 30, 2019 8:26 pm
- Forum: Empirical & Molecular Formulas
- Topic: Empirical Formula
- Replies: 7
- Views: 423
Re: Empirical Formula
You only assume that the sample mass is 100g to make the calculations easier. Because percentages are on a scale of 1-100, assuming that the sample mass is 100g allows you to skip a step and just convert the percentages to masses by changing the units from a percent sign to grams.