Search found 62 matches
- Sun Mar 17, 2019 12:39 am
- Forum: Administrative Questions and Class Announcements
- Topic: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
- Replies: 179
- Views: 22913
Re: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
For kinetics ws pt 1 number 5 why isn't C included in the rate law? Is it an intermediate? if so, how can you tell?
- Sun Mar 17, 2019 12:29 am
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: Units k
- Replies: 3
- Views: 614
Units k
how do you determine units for rate constant?
- Sat Mar 16, 2019 11:23 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: ln k and 1/t
- Replies: 3
- Views: 655
Re: ln k and 1/t
yes
- Sat Mar 16, 2019 11:21 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Elementary Rxns
- Replies: 2
- Views: 489
Elementary Rxns
what would the rate law be for 2A+2B->C be? Do you use the coefficients given for the order or no?
- Sat Mar 16, 2019 11:13 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Ea
- Replies: 1
- Views: 486
Ea
What is the explicit equation for activation energy?
- Sat Mar 16, 2019 10:58 pm
- Forum: Experimental Details
- Topic: Rate law in multiple step reactions [ENDORSED]
- Replies: 3
- Views: 1155
Re: Rate law in multiple step reactions [ENDORSED]
You must replace the intermediates with their equal rate law expressions using the molar ratios when needed.
- Sat Mar 16, 2019 10:49 pm
- Forum: First Order Reactions
- Topic: pseudo first order [ENDORSED]
- Replies: 5
- Views: 913
Re: pseudo first order [ENDORSED]
So is it technically a second order reaction, but because one of the concentrations is so big its basically constant?
- Sat Mar 16, 2019 10:46 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Orientation
- Replies: 2
- Views: 493
Orientation
What are the notes referring to when they say the orientations of colliding molecules must be the same?
- Sat Mar 16, 2019 10:45 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: Units and order
- Replies: 3
- Views: 561
Units and order
Can the order of the reaction be determined by the units? I saw something that to solve for n (order) you can use M^1-n ?
- Sat Mar 16, 2019 10:37 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: ln k and 1/t
- Replies: 3
- Views: 655
ln k and 1/t
When is the profile lnk vs 1/t and when is the profile lnk vs t?
- Sat Mar 16, 2019 7:44 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Transition State
- Replies: 3
- Views: 369
Transition State
What is the transition state and where does it go on the profile?
- Sat Mar 16, 2019 7:39 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Ka and K
- Replies: 1
- Views: 385
Ka and K
What are the steps to find Ka after solving for K in the Nernst equation?
- Sat Mar 16, 2019 7:34 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Reaction Profiles
- Replies: 1
- Views: 147
Reaction Profiles
How does the profile change if it is endergonic vs exergonic?
- Sat Mar 16, 2019 7:33 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Approaches to mechanisms
- Replies: 2
- Views: 313
Approaches to mechanisms
What is the difference between steady state and pre eq approaches?
- Sat Mar 16, 2019 7:29 pm
- Forum: General Rate Laws
- Topic: Rate Constant
- Replies: 1
- Views: 429
Rate Constant
what is the relationship between rate of reaction, rate constant, and half life?
- Sat Mar 16, 2019 6:19 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: E* +/-
- Replies: 1
- Views: 376
E* +/-
Should the calculated E* value when adding E*s from half reactions always be positive?
- Sat Mar 16, 2019 6:18 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Inert Conductor
- Replies: 3
- Views: 346
Inert Conductor
How do you know which inert conductor to add Pt vs Hg?
- Sat Mar 16, 2019 6:16 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Standard of Formation
- Replies: 1
- Views: 377
Standard of Formation
How do you know if you're are given the standard free energy of formation versus just free energy?
- Sat Mar 16, 2019 6:13 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Calculating E*
- Replies: 1
- Views: 427
Calculating E*
When can you add the E* for each half reaction to get the cell E* and when can you not add them because its not a state function? This came up in Lyndon's review when we had to convert E* to delta G.
- Tue Feb 26, 2019 11:03 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Vant Hoff Equation
- Replies: 3
- Views: 358
Re: Vant Hoff Equation
It depends on what you are given but most of the time if you are trying to find K but you're given delta H and delta S (or vice versa)
- Tue Feb 26, 2019 1:18 am
- Forum: Balancing Redox Reactions
- Topic: Standard Potential
- Replies: 2
- Views: 264
Standard Potential
if the coefficients are proportional but different in the same 2 reactions, do you need to multiply E by the molar proportion or does it stay the same?
- Tue Feb 26, 2019 1:00 am
- Forum: Administrative Questions and Class Announcements
- Topic: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
- Replies: 179
- Views: 22913
Re: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
In the Gibbs WS #4 how do you find T? or can you just assume its at 25 C?
- Tue Feb 26, 2019 12:45 am
- Forum: Administrative Questions and Class Announcements
- Topic: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
- Replies: 179
- Views: 22913
Re: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
On #1 of the Gibbs to find the standard enthalpy and entropy of formation you have to do the sum of products minus the sum of the reactants using the numbers given right? For some reason I am not getting the same answer.
- Mon Feb 04, 2019 12:59 am
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Thermos
- Replies: 4
- Views: 526
Thermos
Why is a thermos considered an isolated system and not a closed system?
- Mon Feb 04, 2019 12:58 am
- Forum: Calculating Work of Expansion
- Topic: Integral calculations
- Replies: 4
- Views: 492
Integral calculations
When do you know to take the integral when finding work?
- Mon Feb 04, 2019 12:57 am
- Forum: Phase Changes & Related Calculations
- Topic: Heat and Condensation
- Replies: 9
- Views: 897
Heat and Condensation
Is heat absorbed or released during condensation?
- Mon Feb 04, 2019 12:57 am
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: isothermal expansion
- Replies: 2
- Views: 324
isothermal expansion
What is isothermal expansion?
- Mon Feb 04, 2019 12:56 am
- Forum: Phase Changes & Related Calculations
- Topic: Reversible changes
- Replies: 1
- Views: 184
Reversible changes
What changes to a system are reversible and which are irreversible?
- Mon Feb 04, 2019 12:53 am
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Isothermic definition
- Replies: 5
- Views: 854
Isothermic definition
What is the difference between isothermal and isometric?
- Fri Jan 11, 2019 4:14 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Inert Gases
- Replies: 2
- Views: 145
Inert Gases
Why does adding inert gases only affect the equilibrium constant in a closed system?
- Fri Jan 11, 2019 4:11 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Adding a liquid
- Replies: 7
- Views: 524
Re: Adding a liquid
I believe the only variable that affects K is temperature.
- Fri Jan 11, 2019 4:07 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Solids and Liquids in Rxn
- Replies: 6
- Views: 583
Solids and Liquids in Rxn
What would K be if the reaction was only made up of solids and liquids, no gases or aq solutions?
- Sat Dec 08, 2018 12:32 am
- Forum: Calculating the pH of Salt Solutions
- Topic: Atoms that don't affect pH
- Replies: 3
- Views: 508
Atoms that don't affect pH
How do you know which atoms affect the pH of a solution and which ones do not? For example in NH4Br how do you know not to include Br in the chemical equation?
- Fri Dec 07, 2018 9:14 pm
- Forum: Amphoteric Compounds
- Topic: Amphoteric compounds
- Replies: 2
- Views: 261
Amphoteric compounds
How do you know if a compound can be amphoteric?
- Fri Dec 07, 2018 9:10 pm
- Forum: Amphoteric Compounds
- Topic: Amphoteric
- Replies: 4
- Views: 569
Amphoteric
Are amphoteric and amphoprotic opposite properties? if not, what is the relationship between the two?
- Mon Dec 03, 2018 12:59 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Hydronium
- Replies: 4
- Views: 459
Hydronium
Why is hydronium sometimes referred to as H3O+ and sometimes as H+? What is the difference?
- Mon Dec 03, 2018 12:42 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Electronegativity and delocalization
- Replies: 1
- Views: 302
Electronegativity and delocalization
If an atom has a high electronegativity does it have a strong delocalization power too? Or weak delocal power?
- Mon Dec 03, 2018 12:29 pm
- Forum: Lewis Acids & Bases
- Topic: Lewis v. Bronsted
- Replies: 2
- Views: 293
Lewis v. Bronsted
Whats the difference between Lewis acids and bases and bronsted acids and bases?
- Mon Dec 03, 2018 12:16 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Calculating pH
- Replies: 3
- Views: 361
Calculating pH
When calculating pH do you only ever use the H3O+ concentration or will you ever use OH-?
- Tue Nov 27, 2018 1:15 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: I3-
- Replies: 1
- Views: 199
I3-
Would I3 ^1- (Iodine) be polar or non polar? its linear with 3 lone pairs on the central atom but is there any net dipole?
- Tue Nov 27, 2018 1:04 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 Dipole
- Replies: 1
- Views: 126
Induced Dipole
Will nonpolar molecules always have induced dipole forces?
- Mon Nov 26, 2018 11:08 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: Dipole Forces
- Replies: 3
- Views: 372
Dipole Forces
What is the difference between induced dipole and dipole? How do forces between them differ based on what combination you have?
- Sun Nov 25, 2018 2:09 pm
- Forum: Hybridization
- Topic: sp orbitals
- Replies: 3
- Views: 317
sp orbitals
what do the 2 and 3 mean in sp2, sp3, sp3d2 etc orbitals?
- Sun Nov 25, 2018 10:46 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Naming
- Replies: 4
- Views: 235
Naming
Several times in lecture Dr. Lavelle said the shape would be one thing if looking at lone pairs, however it would be named differently. How do we know when to name it correctly based on regions of e- density and when to just give the general shape that considers lone pairs?
- Sun Nov 25, 2018 10:41 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: pi and sigma bonds
- Replies: 9
- Views: 1389
pi and sigma bonds
Which bond has more energy pi or sigma?
- Sat Nov 24, 2018 2:59 pm
- Forum: Hybridization
- Topic: Steps to figure out hybridization
- Replies: 3
- Views: 472
Steps to figure out hybridization
Do you have to figure the lewis dot and/or VSEPR model to get the right hybridization? What are the steps to figure out if something needs hybridization?
- Wed Nov 14, 2018 10:33 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Molecular Shape
- Replies: 4
- Views: 342
Molecular Shape
Why are molecules considered octahedral that only have 6 bonds?
- Wed Nov 14, 2018 10:31 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angles
- Replies: 3
- Views: 274
Bond Angles
Why are some bond angles exactly 120 or 109.5 while others say they are slightly less than that?
- Sat Nov 10, 2018 7:19 pm
- Forum: Bond Lengths & Energies
- Topic: Bond Lengths
- Replies: 5
- Views: 693
Bond Lengths
If we are asked to predict bond lengths is it just finding the average based on numbers given to you? How could you determine bond lengths if you weren't given any additional information?
- Sat Nov 10, 2018 7:16 pm
- Forum: Dipole Moments
- Topic: Hydrogen Bonds
- Replies: 20
- Views: 1454
Hydrogen Bonds
Relative to other types of bonds, how strong are hydrogen bonds?
- Sat Nov 10, 2018 7:10 pm
- Forum: Electronegativity
- Topic: Electronegativity
- Replies: 3
- Views: 493
Electronegativity
Whats the difference between electronegativity and ionization energy?
- Sat Nov 10, 2018 6:58 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Polarizability Trend
- Replies: 6
- Views: 6373
Re: Polarizability Trend
Polarizability follows the same trend as atomic radius: increasing right to left and increasing down a group
- Sun Nov 04, 2018 10:02 pm
- Forum: Lewis Structures
- Topic: Expanded Octet Rule
- Replies: 4
- Views: 451
Expanded Octet Rule
When a structure includes atoms with expanded octets what the max number of electrons that can be held? Is it 10 because of the d orbital or can it be more?
- Sun Nov 04, 2018 10:00 pm
- Forum: Lewis Structures
- Topic: Expanded Octet Rule
- Replies: 1
- Views: 79
Expanded Octet Rule
When a structure includes atoms with expanded octets what the max number of electrons that can be held? Is it 10 because of the d orbital or can it be more?
- Sun Nov 04, 2018 9:57 pm
- Forum: Lewis Structures
- Topic: Resonance structures
- Replies: 2
- Views: 149
Resonance structures
When a test question asks for resonance structures should we show all possible ones or only the most logical ones?
- Sun Nov 04, 2018 9:53 pm
- Forum: Lewis Structures
- Topic: Garlic Bread 12a
- Replies: 5
- Views: 524
Garlic Bread 12a
How do you determine the number of bonds you should use between Carbon and nitrogen/carbon and carbon/oxygen? Also is there a method to determining where the hydrogens should be placed or can you just do whatever works for the total number of valence e-?
- Sun Oct 21, 2018 9:28 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Particle Size
- Replies: 3
- Views: 347
Particle Size
As explained in the lecture we can know the momentum and position of a large object such as a baseball going through the detectors but not an electron because it is so small that the detectors interfere with its path. My question is do particles larger than electrons react in the same way? or would ...
- Sun Oct 21, 2018 9:17 pm
- Forum: Properties of Electrons
- Topic: Energy Levels and Electrons
- Replies: 1
- Views: 174
Energy Levels and Electrons
When an electron is excited to an n=2 or n=3 etc. state how long does it take to return to the threshold level where it emits a photon?
- Sun Oct 21, 2018 9:14 pm
- Forum: Properties of Electrons
- Topic: Wave Properties
- Replies: 4
- Views: 380
Wave Properties
Can other particles (non electrons) have wave-like properties too?
- Sun Oct 07, 2018 10:03 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Actual/Theoretical Yield
- Replies: 8
- Views: 4228
Actual/Theoretical Yield
Should we know why actual yield is lower than theoretical yield in the way specific to the problem or just know the general reasons that actual yield is less than theoretical yield?
- Sun Oct 07, 2018 9:56 pm
- Forum: Empirical & Molecular Formulas
- Topic: Limiting Reactants
- Replies: 3
- Views: 587
Limiting Reactants
When finding limiting reagents, how do you know what product to compare moles to if not directly stated in the problem? I noticed several module problems that said what is the limiting reactant for the product created? However, there was more than one product in the reaction.
- Sun Oct 07, 2018 9:50 pm
- Forum: Empirical & Molecular Formulas
- Topic: Converting Units
- Replies: 5
- Views: 500
Converting Units
When multiple units are defined in a reaction, is it best to convert to equal units before writing out a reaction? Or will it still be a valid answer if units are converted at the end?