Search found 106 matches
- Wed Mar 11, 2020 4:21 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Instantaneous Rate
- Replies: 41
- Views: 2247
Re: Instantaneous Rate
The instantaneous rate should decrease with time.
- Wed Mar 11, 2020 4:20 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: finding k
- Replies: 3
- Views: 258
Re: finding k
I think you would need experimental data to determine this.
- Wed Mar 11, 2020 4:17 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: dilutions and Ecell
- Replies: 16
- Views: 3351
Re: dilutions and Ecell
It depends on where the dilution takes place but diluting the cathode solution should decrease the cell potential.
- Wed Mar 11, 2020 4:16 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: salt bridge
- Replies: 11
- Views: 663
Re: salt bridge
Salt bridge is usually made of inert anions and cations that balance out charge buildup.
- Wed Mar 11, 2020 4:12 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Change in Ecell
- Replies: 5
- Views: 345
Re: Change in Ecell
Since the electrode is a solid it is not factored into the equilibrium constant and therefore increasing or decreasing its mass will not affect the Ecell.
- Sun Mar 08, 2020 8:03 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Electrode masses
- Replies: 8
- Views: 578
Re: Electrode masses
cell potential does not change with the mass of electrodes.
- Sun Mar 08, 2020 8:02 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: galvanic vs electrolytic
- Replies: 12
- Views: 903
Re: galvanic vs electrolytic
A galvanic cell prodices electrical energy and an electrolytic cell produces chemical energy.
- Sun Mar 08, 2020 7:58 pm
- Forum: General Rate Laws
- Topic: Fractional order and negative orders
- Replies: 3
- Views: 346
Re: Fractional order and negative orders
I don't think we need to know about fractional and negative orders.
- Sun Mar 08, 2020 7:56 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Solids/Liquids
- Replies: 3
- Views: 282
Re: Solids/Liquids
I think the "concentration" of solids and liquids is not included in the rate law.
- Sun Mar 08, 2020 7:42 pm
- Forum: Interesting Applications: Rechargeable Batteries (Cell Phones, Notebooks, Cars), Fuel Cells (Space Shuttle), Photovoltaic Cells (Solar Panels), Electrolysis, Rust
- Topic: Types of Batteries
- Replies: 8
- Views: 586
Re: Types of Batteries
Rechargeable batteries use reversible chemical reactions. Chemical reactions used in non rechargeable batteries are irreversible when a current is passed in the reverse direction
- Sun Mar 08, 2020 7:29 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Application
- Replies: 6
- Views: 500
Re: Application
I can think of two main ones: G=-nFE and G=-RTlnQ
- Sun Mar 01, 2020 2:20 pm
- Forum: Balancing Redox Reactions
- Topic: H+ or H2O
- Replies: 9
- Views: 632
Re: H+ or H2O
H2O is used to intially balance the oxygens, then H+ to balance the hydrogens, and then e- to balance the charge.
- Sun Mar 01, 2020 2:19 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: 6N.5(b)
- Replies: 1
- Views: 196
Re: 6N.5(b)
I think these are the half reactions:
Cl-(aq) --> Cl2(g) + 2e-
MnO4- + 5e- --> Mn2+
Cl-(aq) --> Cl2(g) + 2e-
MnO4- + 5e- --> Mn2+
- Sun Mar 01, 2020 2:17 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: salt bridge
- Replies: 11
- Views: 680
Re: salt bridge
To prevent charge buildup
- Sun Mar 01, 2020 2:17 pm
- Forum: General Rate Laws
- Topic: temp
- Replies: 2
- Views: 205
Re: temp
You would need experimental data to find the rate of the reaction. I don't think its possible to determine the effects of the temp change without experimental data.
- Sat Feb 22, 2020 2:10 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Vant Hoff Equation vs dG = -RTln(K)
- Replies: 1
- Views: 178
Re: Vant Hoff Equation vs dG = -RTln(K)
You will have a different K at different temperatures since the equilibrium concentrations vary with temperature.
- Sat Feb 22, 2020 2:07 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: 5G.21
- Replies: 4
- Views: 560
Re: 5G.21
You can find the K using the delta g value and the delta G0 value. The van't hoff equation may help.
- Sat Feb 22, 2020 2:03 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: n in -nFE
- Replies: 12
- Views: 887
Re: n in -nFE
The n in -nFE represents the mole of electrons transferred in a redox reaction.
- Sat Feb 22, 2020 2:02 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Salt Bridge
- Replies: 5
- Views: 562
Re: Salt Bridge
A salt bridge will contain stable anions and cations like Na+ and NO3- which will migrate to the anode and cathodes to prevent charge buildup when electrons flow from the anode to the cathode.
- Sat Feb 22, 2020 2:00 pm
- Forum: Phase Changes & Related Calculations
- Topic: delta G0 versus delta G
- Replies: 15
- Views: 2610
Re: delta G0 versus delta G
Delta G0 is given under standard conditions whereas delta G is given for modified conditions.
- Sun Feb 16, 2020 9:07 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: S = 0
- Replies: 21
- Views: 1185
Re: S = 0
Entropy can also equal zero at absolute zero when the molecules only have one orientable state (no residual entropy).
- Sun Feb 16, 2020 9:06 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: How to interpret reversible/irreversible graphs
- Replies: 6
- Views: 698
Re: How to interpret reversible/irreversible graphs
For a pressure versus volume graph a reversible process, which is usually isothermic, will be a curved line. An irreversible reaction will be a straight line.
- Sun Feb 16, 2020 9:05 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Isochoric
- Replies: 8
- Views: 605
Re: Isochoric
Isochoric means at the same volume.
- Sun Feb 16, 2020 9:04 pm
- Forum: Balancing Redox Reactions
- Topic: Redox Reactions
- Replies: 12
- Views: 577
Re: Redox Reactions
A redox reaction is any reaction in which the oxidation numbers of an atom is changed by the transfer of electrons.
- Sun Feb 16, 2020 9:03 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: When to use the different equations
- Replies: 5
- Views: 451
Re: When to use the different equations
You want to use the equation with ln in it when you are trying to figure out the delta G at non-equilibrium concentrations.
- Wed Feb 05, 2020 2:29 am
- Forum: Calculating Work of Expansion
- Topic: Work on a system +/-
- Replies: 4
- Views: 151
Re: Work on a system +/-
If work is being done on the system the free energy is increasing because the external environment is transferring energy to the internal system and when the system is doing work like expansion that energy is being transferred outside.
- Wed Feb 05, 2020 2:26 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Reversible vs Irreversible
- Replies: 4
- Views: 261
Re: Reversible vs Irreversible
Reversible reactions will have a Kc between 10^-3 and 10^3
- Wed Feb 05, 2020 2:23 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Cv and Cp
- Replies: 3
- Views: 99
Re: Cv and Cp
At constant volume, the heat goes towards raising temperature but at constant pressure, some go towards work.
- Wed Feb 05, 2020 2:19 am
- Forum: Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy
- Topic: Entropy in an isolated system
- Replies: 3
- Views: 207
Re: Entropy in an isolated system
Maximum means that all possible energy states have been realized.
- Wed Feb 05, 2020 2:10 am
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: HW 4F.1
- Replies: 5
- Views: 207
Re: HW 4F.1
I think you would need to first relate the work to heat and then heat to entropy as shown in class today.
- Tue Jan 28, 2020 6:14 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Closed vs isolated systems
- Replies: 24
- Views: 907
Re: Closed vs isolated systems
A closed system cannot exchange mass with its surroundings but it can exchange energy, while an isolated system cannot exchange either.
- Tue Jan 28, 2020 6:10 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: 4A7
- Replies: 4
- Views: 191
Re: 4A7
That is the specific heat of water, the amount of energy needed to raise one gram of water one degree celcius.
- Tue Jan 28, 2020 6:05 pm
- Forum: Phase Changes & Related Calculations
- Topic: Burns
- Replies: 4
- Views: 193
Re: Burns
Steam at 100 degrees will contain more energy than water at 100 degrees because of the phase change (the flat line on the heating curve).
- Tue Jan 28, 2020 6:03 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Bond Enthalpies
- Replies: 11
- Views: 298
Re: Bond Enthalpies
Using this method is less accurate and takes longer because all the bonds need to be broken and reformed. It is less accurate because the bond enthalpies are averages, not exact values.
- Tue Jan 28, 2020 5:56 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Hess's Law
- Replies: 11
- Views: 379
Re: Hess's Law
Hess's law is used to find the change in enthalpy. It states that regardless of the pathway taken to reach a final product, the change in enthalpy will be the same. This is because enthalpy is a state function.
- Thu Jan 23, 2020 12:51 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Water in K constant
- Replies: 6
- Views: 264
Re: Water in K constant
water is included in the Kp expression if it is a vapor.
- Thu Jan 23, 2020 12:48 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Buffers
- Replies: 3
- Views: 134
Re: Buffers
We're not at buffers yet, I don't think you'll need to do a buffer problem.
- Thu Jan 23, 2020 12:40 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: State Properties and q vs H
- Replies: 2
- Views: 125
Re: State Properties and q vs H
Delta H and q measure two different things even though they may be related. Q measures work while dH measures enthalpy which only depends on initial and final conditions.
- Thu Jan 23, 2020 12:36 pm
- Forum: Ideal Gases
- Topic: solids and K
- Replies: 8
- Views: 350
Re: solids and K
Solids are not in solution because they are not dissolved, and thus there exists no concentration for solids. solids function as a pure substance
- Thu Jan 23, 2020 12:35 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 5% rule
- Replies: 13
- Views: 635
Re: 5% rule
When you cancel out the x and solve. You see if the x value is less than 5% afterwards.
- Mon Jan 20, 2020 9:31 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: parts of salts that don't affect pH
- Replies: 4
- Views: 174
Re: parts of salts that don't affect pH
All strong acid and base cations/anions will not affect the pH of the solution.
- Mon Jan 20, 2020 9:30 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: new Kc value when combining equations
- Replies: 2
- Views: 102
Re: new Kc value when combining equations
You multiply the two kc values.
- Mon Jan 20, 2020 9:30 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Equilibrium constants vs equilibrium of the P&R
- Replies: 3
- Views: 131
Re: Equilibrium constants vs equilibrium of the P&R
The equilibrium constant will only change when there is a change in the temperature. Otherwise, the Kc does not change, only the Q will change.
- Mon Jan 20, 2020 9:28 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: 6.19
- Replies: 1
- Views: 148
Re: 6.19
I think it would be good to know this information just in case it shows up on the test.
- Mon Jan 20, 2020 9:27 pm
- Forum: Calculating the pH of Salt Solutions
- Topic: NH4F
- Replies: 2
- Views: 662
Re: NH4F
I think this would produce both an acid and base in water. The Ka and Kb values would need to be compared to determine which character would be prevalent.
- Sun Jan 12, 2020 2:20 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Increased Pressure by Inert Gas
- Replies: 2
- Views: 90
Re: Increased Pressure by Inert Gas
Inert gases do not affect the equilibriums of the gases already in the container because they are not part of the reaction.
- Sun Jan 12, 2020 2:10 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Kc vs Kp
- Replies: 10
- Views: 303
Re: Kc vs Kp
Kc and Kp would not be the same values and i think there is a way to convert between the two for gases.
- Sun Jan 12, 2020 2:08 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Test 1
- Replies: 2
- Views: 160
Re: Test 1
Im assuming it will be on outline 1 and parts of outline 2.
- Sun Jan 12, 2020 2:07 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 5I. 19
- Replies: 3
- Views: 164
Re: 5I. 19
If you know 60% reacted then you know the moles that were used and you can use that to find the leftover moles for the other reactant and the moles of product made. You can use these new concentrations to find the equilibrium constant.
- Sun Jan 12, 2020 2:05 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Homework 5G.1 Help
- Replies: 4
- Views: 351
Re: Homework 5G.1 Help
For pressure the equilibrium moves towards the side with the lower moles, what Dr. Lavelle showed in class Friday.
- Thu Dec 05, 2019 5:26 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: Hydrogen Bonding
- Replies: 2
- Views: 118
Re: Hydrogen Bonding
There are 4 spots for hydrogen bonding on H20
- Thu Dec 05, 2019 5:26 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Ligands
- Replies: 1
- Views: 172
Re: Ligands
This depends on the flexibility of the ligand (whether it can rotate) and the locations of the lone pairs. Might be best to just memorize the sheet that is on the website because its difficult to determine the denticity sometimes.
- Thu Dec 05, 2019 5:18 pm
- Forum: Calculating the pH of Salt Solutions
- Topic: Wednesday Lecture 12/4
- Replies: 4
- Views: 393
Re: Wednesday Lecture 12/4
You do not need to know this for the test if I am right. I think that was all an introduction for Chem 14b.
- Thu Dec 05, 2019 5:18 pm
- Forum: Amphoteric Compounds
- Topic: 6A #11
- Replies: 2
- Views: 99
Re: 6A #11
The bicarbonate ion will react with a H30+ when it is acting like a base to make carbonic acid and water.
- Thu Dec 05, 2019 5:17 pm
- Forum: Naming
- Topic: Ammine vs. Amine
- Replies: 1
- Views: 204
Re: Ammine vs. Amine
NH4+ is not a ligand if I am right. I think the other two are just spelling conventions.
- Thu Dec 05, 2019 5:16 pm
- Forum: Naming
- Topic: Question 9C1
- Replies: 1
- Views: 106
Re: Question 9C1
This is just the convention for iron based on its latin name and periodic symbol.
- Fri Nov 29, 2019 2:00 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: strength of ligands
- Replies: 1
- Views: 98
Re: strength of ligands
probably stronger b/c there is direct electron sharing in the bonds for coordination compounds.
- Fri Nov 29, 2019 1:59 am
- Forum: Acidity & Basicity Constants and The Conjugate Seesaw
- Topic: calculating pKa and pKb
- Replies: 2
- Views: 243
Re: calculating pKa and pKb
i think the sum of the pKa and pKb should be 14.
- Fri Nov 29, 2019 1:58 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: water
- Replies: 1
- Views: 104
Re: water
Water is not large enough to wrap around and bind in two places. The lone pairs are only on the oxygen, they need to be physically spread apart by being on two different atoms for a ligand to be a polydentate.
- Fri Nov 29, 2019 1:57 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: coordination number
- Replies: 8
- Views: 442
Re: coordination number
I think the coordination number is based on the number of ligands bound to the transition metal. I'm guessing lone pairs may play a role in determining how many ligands can bind to the transition metal.
- Fri Nov 29, 2019 1:54 am
- Forum: Amphoteric Compounds
- Topic: acids/bases
- Replies: 2
- Views: 98
Re: acids/bases
I think this would depend on the presence of other compounds present in solution. Also would depend on the concentration of OH- or H30+ in the water, since amphoteric compounds act like a buffer. If I remember correctly the pKa of the buffer (amphoteric compound) is what the solution will try to bal...
- Sat Nov 23, 2019 2:46 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Oxalato
- Replies: 3
- Views: 259
Re: Oxalato
I think it is 2-
- Sat Nov 23, 2019 2:45 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Transition Metals
- Replies: 2
- Views: 222
Re: Transition Metals
I think this means that the metal is inorganic but it is bound to organic ligands like diethyldiamine.
- Sat Nov 23, 2019 2:43 pm
- Forum: Naming
- Topic: [Co(NH3)5Cl]Cl H2O
- Replies: 4
- Views: 350
Re: [Co(NH3)5Cl]Cl H2O
There is a naming sheet for ligands. You just need to memorize these
- Sat Nov 23, 2019 2:43 pm
- Forum: Hybridization
- Topic: Hybridization Structure
- Replies: 3
- Views: 257
Re: Hybridization Structure
you count the number of lone pairs + bonds (regardless of bond type). for example, 2 bonds with one lone pair would be sp2. 2 bonds by themselves would be sp.
- Sat Nov 23, 2019 2:42 pm
- Forum: Naming
- Topic: Textbook question 9C.1
- Replies: 2
- Views: 225
Re: Textbook question 9C.1
if the question is aqua v hydrate, aqua refers to water that is within the coordination sphere and bound to the transition metal.
- Fri Nov 15, 2019 1:33 pm
- Forum: Dipole Moments
- Topic: IMFs
- Replies: 2
- Views: 143
Re: IMFs
You need to understand VSEPR theory and atomic trends to help you determine the type of IM force present.
- Fri Nov 15, 2019 1:23 pm
- Forum: Sigma & Pi Bonds
- Topic: One Sigma One Pi
- Replies: 3
- Views: 229
Re: One Sigma One Pi
when a double bond is formed, you have one sigma bond or an S orbital interaction and one pi bond or p orbital interaction which fixes the bond in place (non-rotatable). you can only have on sigma bond b/c there is only one s orbital.
- Fri Nov 15, 2019 1:19 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: Atom size vs. boiling point
- Replies: 4
- Views: 579
Re: Atom size vs. boiling point
Larger molecules and atoms are also more massive, and therefore, it takes more energy to make that substance change states.
- Fri Nov 15, 2019 1:15 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: induced dipoles
- Replies: 5
- Views: 351
Re: induced dipoles
Induced dipoles occur when polar molecules cause shifts in the electron density of non-polar molecules.
- Fri Nov 15, 2019 1:13 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Inter-molecular Electron Repulsion
- Replies: 6
- Views: 280
Re: Inter-molecular Electron Repulsion
You can also think of strength by how diffuse each type of pair is. Therefore, because the lone pair is the most diffuse, it is the most repulsive. Lone pairs also have lower effective nuclear charge acting on them.
- Sat Nov 09, 2019 10:53 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: what is electron distortion?
- Replies: 3
- Views: 156
Re: what is electron distortion?
Electron distortion is when electron densities are shifted. This can only happen if electrons are loosely held so they can move more, or in other words, an atom that is more polarizable.
- Sat Nov 09, 2019 10:42 pm
- Forum: Dipole Moments
- Topic: Dipole Bonds
- Replies: 1
- Views: 130
Re: Dipole Bonds
When two polar molecules interact that is a simple dipole dipole interaction where the positive regions of the opposing molecules align with the negative regions of the other. Dipole induced dipole induced occurs when electron densities shift spontaneously and positive and negative regions randomly ...
- Sat Nov 09, 2019 10:39 pm
- Forum: Bond Lengths & Energies
- Topic: how to determine the energy of a bond
- Replies: 6
- Views: 563
Re: how to determine the energy of a bond
Usually the length (which correlates to strength) of a bond is a factor that determines the energy stored in a bond. These values are determined experimentally, however.
- Sat Nov 09, 2019 10:38 pm
- Forum: Dipole Moments
- Topic: Instantaneous dipoles
- Replies: 2
- Views: 88
Re: Instantaneous dipoles
Instantaneous dipoles occur in all molecules. Electrons exist in the orbitals which are in theory just regions where the electron is most probably found. These electrons are in continuous motion all across the molecule, and therefore, they may randomly and spontaneously congregate in one region crea...
- Sat Nov 09, 2019 10:27 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: Instantaneous dipole moment
- Replies: 5
- Views: 176
Re: Instantaneous dipole moment
Instantaneous dipole moments, like Van der Waals forces, last for fractions of seconds in the sense that the electron densities continually shift causing continual and sporadic interactions in different regions of the two molecules.
- Sun Nov 03, 2019 8:59 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: L quantum number
- Replies: 5
- Views: 421
L quantum number
If n is 12 what can l be? What can ml be?
- Sun Nov 03, 2019 8:46 pm
- Forum: Ionic & Covalent Bonds
- Topic: polarizability
- Replies: 2
- Views: 200
polarizability
Does polarizability apply to both cations and anions?
- Sun Nov 03, 2019 8:40 pm
- Forum: Octet Exceptions
- Topic: Expanded Octets
- Replies: 5
- Views: 223
Expanded Octets
Whats the maximum number of electrons an expanded octet can have?
- Thu Oct 31, 2019 5:36 pm
- Forum: Lewis Structures
- Topic: Sulfur Dioxide
- Replies: 2
- Views: 147
Sulfur Dioxide
What would be three resonance structures for SO2? Having S with an expanded octet and two double bonds and a lone pair seems to be the most stable due to formal charge. However, experimental evidence suggests that there is one single and one double bond on the S. On the test if we were given a quest...
- Thu Oct 31, 2019 5:29 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Atomic Spectra- not as particle
- Replies: 1
- Views: 79
Re: Atomic Spectra- not as particle
I think that amplitude would determine energy if light acted as a classical wave and any light with enough intensity could excite electrons if shined at the right amplitude.
- Thu Oct 31, 2019 5:20 pm
- Forum: Dipole Moments
- Topic: How to draw the dipole moment
- Replies: 2
- Views: 204
Re: How to draw the dipole moment
This hasn't been discussed yet, but I am more familiar with the arrow pointing towards the more negative region since the electrons would shift that way.
- Thu Oct 31, 2019 5:17 pm
- Forum: Photoelectric Effect
- Topic: HW 1.3
- Replies: 1
- Views: 119
Re: HW 1.3
Probably just a typo. The problem does ask for power so Watts is the correct unit
- Tue Oct 29, 2019 6:36 pm
- Forum: Dipole Moments
- Topic: Dimethyl Ether
- Replies: 1
- Views: 100
Dimethyl Ether
Does dimethyl ether make a hydrogen bond?
- Wed Oct 23, 2019 5:33 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration Exceptions:
- Replies: 3
- Views: 151
Re: Electron Configuration Exceptions:
An electron is moved from the s subshell to the d subshell when an atom is at d^4 because then all the subshells would be singly filled and this is more stable.
- Wed Oct 23, 2019 5:26 pm
- Forum: SI Units, Unit Conversions
- Topic: Sharing of electrons
- Replies: 3
- Views: 320
Re: Sharing of electrons
Are you referring to nodes? Electrons exist in hybridized orbitals when molecules form.
- Wed Oct 23, 2019 5:23 pm
- Forum: Electronegativity
- Topic: Electronegativity values
- Replies: 3
- Views: 189
Re: Electronegativity values
I don't think we need to be able to calculate electronegativity values right now
- Wed Oct 23, 2019 5:21 pm
- Forum: Electronegativity
- Topic: Electronegativity
- Replies: 14
- Views: 661
Re: Electronegativity
Electronegativity is the measure of an atoms tendency to attract an electron. Atoms at the right of the table are close to filling an octet and are therefore more electronegative.
- Wed Oct 23, 2019 5:17 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration
- Replies: 2
- Views: 181
Re: Electron Configuration
This is done because that adding electrons with parallel spins into different orbitals is a more stable configuration.
- Sat Oct 19, 2019 1:41 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Paired vs Parallel electrons
- Replies: 5
- Views: 128
Re: Paired vs Parallel electrons
Paired e- are electrons that occupy the same orbital in a subhsell with opposite spins. Electrons that independently occupy multiple orbitals in a subshell with the same spin are parallel.
- Wed Oct 16, 2019 8:31 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: 1D #25
- Replies: 1
- Views: 85
Re: 1D #25
A and C do not work. Correlate each subshell to its quantum number.
- Wed Oct 16, 2019 8:26 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: 1D #19
- Replies: 1
- Views: 62
Re: 1D #19
(a)3 (b) 5 (c) 1 (d)7
Correlate subshells to l values. Ex. p is 1
Correlate subshells to l values. Ex. p is 1
- Wed Oct 16, 2019 8:25 pm
- Forum: Properties of Electrons
- Topic: 1B.15
- Replies: 4
- Views: 143
Re: 1B.15
You can use De Broglie's equation to find the wavelength.
- Wed Oct 16, 2019 8:18 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: 1D #11
- Replies: 3
- Views: 108
Re: 1D #11
a) 1; (b) 5; (c) 3; (d) 7
orbitals for l can be calculated by 2l+1
orbitals for l can be calculated by 2l+1
- Wed Oct 16, 2019 5:33 pm
- Forum: Properties of Light
- Topic: Schrodinger's Equation
- Replies: 4
- Views: 193
Re: Schrodinger's Equation
I think you only need to know the purpose of Schrodinger's Eq., there is no further use of it than that in our class. Know that the square of the wave function represents probablilty density and that the solutions to a wave equation are quantum numbers.
- Wed Oct 09, 2019 6:04 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Spectrum of Atomic Hydrogen
- Replies: 3
- Views: 95
Re: Spectrum of Atomic Hydrogen
I'd start by finding where 102.6 nm falls in the EM spectrum (this will help you understand what series you are in for hydrogen). After this you can calculate the energy for the photon and then find n2.
- Wed Oct 09, 2019 6:02 pm
- Forum: Trends in The Periodic Table
- Topic: Ionization Energy: Na vs. Al
- Replies: 3
- Views: 3960
Re: Ionization Energy: Na vs. Al
Sodium has one unpaired electron in the 3s subshell, thus it is more inclined to lose that electron. If it loses that electron to an electronegative atom like chlorine the subshells are "satisfied" because the valence electrons are balanced in a "full" subshell. Aluminum requires...
- Wed Oct 09, 2019 5:53 pm
- Forum: Properties of Electrons
- Topic: electron energy [ENDORSED]
- Replies: 7
- Views: 535
Re: electron energy [ENDORSED]
As the photon excites the electron it transfers its energy to the electron, thus the electron gaining energy. when the electron falls to its original level it emits a photon of the same energy; it loses energy in this phase as a new photon gains that energy.
- Wed Oct 09, 2019 5:47 pm
- Forum: Properties of Electrons
- Topic: Balmer/Lyman series
- Replies: 5
- Views: 306
Re: Balmer/Lyman series
I know that there was a problem on the quantum hw that said an electron is excited by UV light and knowing the details about the lyman series makes the problem easier.
- Wed Oct 09, 2019 5:30 pm
- Forum: Photoelectric Effect
- Topic: Atomic Spectra [ENDORSED]
- Replies: 3
- Views: 124
Re: Atomic Spectra [ENDORSED]
Just adding to the previous responses, as mentioned in lecture because energy is quantized you need a specific wavelength of light for an electron to jump from one level to a higher energy level. Atomic emission spectra have bands that are isolated in specific regions; like how the Lyman series is i...