Search found 68 matches
- Thu Mar 14, 2019 11:57 pm
- Forum: General Rate Laws
- Topic: Final Equations
- Replies: 4
- Views: 435
Final Equations
Are there any equations that won't be given on the formula sheet that we have to memorize?
- Thu Mar 14, 2019 11:25 pm
- Forum: General Rate Laws
- Topic: Determining rate order
- Replies: 3
- Views: 309
Re: Determining rate order
You determine the order of one reactant each time so you want to pick the experiments where the only variation is the concentration of the reactant you are studying. But say like in 6th edition 15.19 the solutions use experiments 2 and 3, when the concentration of 2 is equal to the concentration of...
- Thu Mar 14, 2019 11:18 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: 6th edition, 15.63
- Replies: 2
- Views: 303
Re: 6th edition, 15.63
I also can't figure this out but it's clear that the solution is flawed because it also says 37'C is equal to 3130 K
- Thu Mar 14, 2019 11:10 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: A in the Arrhenius Equation
- Replies: 4
- Views: 371
Re: A in the Arrhenius Equation
A is just the frequency factor. Basically, if A increases the rate will increase. If you're looking at a plot, lnA is the b in y=mx+b, or the y-intercept.
- Thu Mar 14, 2019 11:06 pm
- Forum: General Rate Laws
- Topic: slow/fast steps
- Replies: 7
- Views: 609
Re: slow/fast steps
my TA said it will tell us
- Thu Mar 14, 2019 11:03 pm
- Forum: *Enzyme Kinetics
- Topic: Adsorption
- Replies: 13
- Views: 3081
Re: Adsorption
Would an adsorption catalyst work differently in an equation? Or should I just know what it is compared to absorption
- Thu Mar 14, 2019 10:58 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Overall Order
- Replies: 5
- Views: 691
Re: Overall Order
It helps for when you're finding the units for k because the units are M^(1-n) x t^-1 where n is the overall order
- Thu Mar 14, 2019 10:52 pm
- Forum: General Rate Laws
- Topic: Final
- Replies: 9
- Views: 1028
Final
Did Lavelle say how harshly he will grade on units/sig figs on the final?
- Thu Mar 14, 2019 10:51 pm
- Forum: General Rate Laws
- Topic: Determining rate order
- Replies: 3
- Views: 309
Determining rate order
How do you know which experiments to use in those charts to determine the orders for each reactant?
- Thu Mar 07, 2019 9:31 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Test 2
- Replies: 4
- Views: 503
Test 2
What was the right answer for the gibbs free energy question on test 2 about rusting? like if it was spontaneous or not? and why?
- Thu Mar 07, 2019 9:30 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Test 2
- Replies: 4
- Views: 451
Test 2
Can someone list the steps for the pH question from test two please
- Mon Feb 25, 2019 7:31 pm
- Forum: Balancing Redox Reactions
- Topic: Friday lecture
- Replies: 1
- Views: 246
Re: Friday lecture
since the anode was reversed and the sign changed, we add -.34 and .77. However, if we didn't reverse it, it would be .77-.34, which would give the same answer. Basically, if you use the voltage from the original voltages given, you subtract it. If you use the reverse anode reaction voltage, you add...
- Mon Feb 25, 2019 7:24 pm
- Forum: Van't Hoff Equation
- Topic: Equilibrium
- Replies: 6
- Views: 695
Re: Equilibrium
it relates to equilibrium because K is the equilibrium constant. It helps to find the K at different temperatures.
- Mon Feb 25, 2019 7:19 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Pressure & K
- Replies: 1
- Views: 208
Re: Pressure & K
K will help tell us if the reaction is spontaneous, nonspontaneous, or at equilibrium, depending on its value. If you increase the partial pressure of the product, deltaG becomes more positive, and if you increase the partial pressure of the reactant, deltaG becomes more negative.
- Mon Feb 25, 2019 7:14 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Nernst Equation
- Replies: 2
- Views: 293
Re: Nernst Equation
it represents the number of moles. however, you find this by balancing the equation and taking the number of electrons into account so that it's balanced.
- Mon Feb 25, 2019 7:13 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cell Diagrams
- Replies: 2
- Views: 249
Re: Cell Diagrams
It's more based on the anode and cathode. So say you have Cu2+(aq) + 2Cr2+ (aq) ---> 2Cr3+(aq) + Cu(s). Since the Cr is the one losing electrons, it will be on the anode side and since Cu is gaining electrons, it will be on the cathode side. So it will look like: Pt(s) | Cr3+, Cr2+(aq) || Cu2+(aq) |...
- Mon Feb 25, 2019 7:07 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing Electrons
- Replies: 3
- Views: 316
Re: Balancing Electrons
finding the number of electrons is based on the change in the molecules. So say there's Cu2+ and it becomes Cu3+, it will have lost an electron and it will look like Cu2+ ---> Cu3+ + e-. Thus, this is the anode and it lost one electron.
- Sun Feb 10, 2019 10:57 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Midterm [ENDORSED]
- Replies: 49
- Views: 4437
Re: Midterm [ENDORSED]
I've never had Lavelle before and I was wondering whether the questions on midterms/finals are mostly math based/problem solving or are there conceptual questions asked as well? They're mostly math based/problem solving but there are still conceptual questions, they're just worth less points./A lot...
- Sun Feb 10, 2019 10:53 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Chem 14 BL
- Replies: 5
- Views: 744
Re: Chem 14 BL
Should 14BL and 14C be taken at the same time to graduate on time?
- Sun Feb 10, 2019 10:51 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: conversions
- Replies: 3
- Views: 289
conversions
Will we have to memorize conversions such as 1 atm=101325 Pa?
- Sun Feb 10, 2019 10:49 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: answer format
- Replies: 4
- Views: 408
answer format
On the midterm does anyone know if we have to convert our answers for delta U into joules? Or can we leave it as L.atm?
- Tue Jan 29, 2019 10:00 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Lecture Question
- Replies: 3
- Views: 291
Lecture Question
In one of the examples from Monday's lecture, O2 didn't have any delta HF value. I was wondering why that is?
- Tue Jan 29, 2019 9:58 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: 6th edition 8.31
- Replies: 2
- Views: 257
6th edition 8.31
How do you find the J/mol/degrees celsius number (sorry I forgot the name of it)? In this question that number was different for constant volume and fro constant pressure but how is it found? Thanks
- Sat Jan 26, 2019 5:02 pm
- Forum: Phase Changes & Related Calculations
- Topic: Modules
- Replies: 17
- Views: 1202
Re: Modules
Do you guys know if he'll add modules for other topics?
- Sat Jan 26, 2019 5:00 pm
- Forum: Phase Changes & Related Calculations
- Topic: Severe burn from steam clarification
- Replies: 5
- Views: 1926
Re: Severe burn from steam clarification
I don't know if I can explain this that well but think of it in terms of that graph Lavelle had on his presentation. It takes about 41 kJ for vapor to become a liquid at 100 degrees Celsius, but it's still at 100 degrees so it has to use even more energy to go to a lower temperature. Meanwhile, it d...
- Sat Jan 26, 2019 4:55 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: method 2
- Replies: 2
- Views: 239
method 2
In method 2 I just wanted to confirm. So when the bonds break on the reactant side that releases energy right? But then it requires energy to form the new bonds on the product side? Does it take the energy from the broken bonds and then is whatever that's left over the net enthalpy?
- Sat Jan 26, 2019 4:53 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: energy production
- Replies: 4
- Views: 497
energy production
Lavelle briefly talked about how one heartbeat takes 1 joule of energy. Does that energy come from the bonds breaking in glucose?
- Sat Jan 26, 2019 4:52 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: method 1
- Replies: 4
- Views: 389
method 1
In method 1, when adding the two equations do you cancel out molecules if there's one on the reactant side and one on the product side?
- Sat Jan 26, 2019 4:51 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: method 1
- Replies: 3
- Views: 307
method 1
In method 1 from the last lecture do the 2 NO's cancel each other out?
- Tue Jan 22, 2019 3:18 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: equations
- Replies: 10
- Views: 690
Re: equations
I meant like it would just say you have molecule A, B, and C. How do you know the equation for that if they just tell you what they are? Like how do you know A and B form C or if C breaks down to form A and B?
- Sun Jan 13, 2019 3:36 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: solids and liquids
- Replies: 5
- Views: 523
solids and liquids
Why don't the molar concentrations of solids and liquids change in a reaction?
- Sun Jan 13, 2019 3:33 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: concentration vs partial pressure
- Replies: 2
- Views: 176
concentration vs partial pressure
Would it be wrong if on a test we used concentration in the K equation if the reaction refers to gases? Or would we have to use partial pressure? (and vice versa for aqueous)
- Sun Jan 13, 2019 3:29 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: equations
- Replies: 10
- Views: 690
equations
For some of the homework questions, it would just say the molecules and not distinguish if they were reactants or products. This is stupid but how do we know which are reactants and which are products?
- Sun Dec 09, 2018 1:34 am
- Forum: Lewis Acids & Bases
- Topic: Acids and Bases affecting the pH
- Replies: 1
- Views: 401
Re: Acids and Bases affecting the pH
If you use a weak acid, it won't completely ionize in solution, so the pH will be higher
- Sun Dec 09, 2018 1:32 am
- Forum: Electronegativity
- Topic: Polarizing Power and Polarizability
- Replies: 2
- Views: 469
Re: Polarizing Power and Polarizability
I know that stronger polarizability has to do with size, so the larger the molecule, the stronger the polarizability. Since Mg2+ has lost two electrons, it'll be smaller than Li+ because that only lost one electron. And then since Br is further down on the periodic table it's larger than P, so it's ...
- Sun Dec 09, 2018 1:27 am
- Forum: Conjugate Acids & Bases
- Topic: Stability of Conjugate Base
- Replies: 6
- Views: 3681
Re: Stability of Conjugate Base
If a conjugate base is more stable, the acid is more likely to donate a proton. So the more stable the conjugate base, the stronger the acid (because it'll donate a proton a lot easier).
- Sun Dec 09, 2018 12:10 am
- Forum: Amphoteric Compounds
- Topic: water
- Replies: 4
- Views: 492
Re: water
but why does water always seem to be in an equilibrium reaction? does it basically mean that if it's mixed with water it will always be switching back and forth between the reactants and products?
- Sat Dec 08, 2018 10:33 pm
- Forum: Amphoteric Compounds
- Topic: water
- Replies: 4
- Views: 492
water
Why are there double arrows in reactions with water?
- Sat Dec 08, 2018 7:54 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: pH
- Replies: 5
- Views: 719
pH
Does pH increase or decrease as H+ concentration increases and why?
- Sat Dec 08, 2018 7:51 pm
- Forum: Naming
- Topic: cis and trans
- Replies: 4
- Views: 501
cis and trans
Do we have to know what cis and trans is for naming? What is that if we do?
Formula
On the naming coordination compounds link it gives the structure for ethylenediaminetetraacetato but I was wondering what the formula for that is? Also, does anyone know if the test only uses the compounds from the naming coordination compounds link?
- Sun Dec 02, 2018 10:04 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: ionization of weak bases
- Replies: 1
- Views: 162
ionization of weak bases
Why aren't weak bases completely ionized in water?
- Sun Dec 02, 2018 10:02 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: charges
- Replies: 1
- Views: 189
charges
This is stupid but are the charges in acid and base reactions found from using formal charge?
- Sun Dec 02, 2018 10:00 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: calcium
- Replies: 2
- Views: 269
calcium
why is calcium oxide called quicklime and calcium hydroxide called slaked lime
- Sun Nov 25, 2018 5:02 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Test 3
- Replies: 38
- Views: 2402
Re: Test 3
I think we need to be able to identify shapes so we might have to know the bond angles
- Sun Nov 25, 2018 4:59 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Polarity
- Replies: 3
- Views: 630
Re: Polarity
I believe it's because it's t-bone shaped and the three dipoles don't cancel each other out, causing it to be polar
- Sun Nov 25, 2018 4:54 pm
- Forum: Hybridization
- Topic: Hw: Ch.4 #43 (6th Edition)
- Replies: 1
- Views: 62
Re: Hw: Ch.4 #43 (6th Edition)
I think s character is like how much s is in a hybridized orbital. So for example in an sp3 orbital, it's 25% s character and 75% p character.
- Tue Nov 13, 2018 2:53 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Biological Activity
- Replies: 3
- Views: 351
Biological Activity
How does the shape and conformation of a molecule determine its biological activity?
- Tue Nov 13, 2018 2:51 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: 11
- Views: 912
hydrogen bonding
How does hydrogen bonding explain higher melting points?
- Tue Nov 13, 2018 2:50 pm
- Forum: *Liquid Structure (Viscosity, Surface Tension, Liquid Crystals, Ionic Liquids)
- Topic: Shape and Boiling Point
- Replies: 12
- Views: 2971
Shape and Boiling Point
What is the relationship between shape and boiling point? Like I know if it's rod-shaped there's a stronger interaction because of the larger distance, but what does that have to do with its higher boiling point?
- Tue Nov 13, 2018 2:46 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: Vapor Pressure
- Replies: 2
- Views: 480
Re: Vapor Pressure
as the intermolecular attraction increases, vapor pressure decreases
- Tue Nov 13, 2018 2:42 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Names and Shapes of molecules
- Replies: 2
- Views: 150
Re: Names and Shapes of molecules
I think it will be however many he teaches us in lecture and I'm 99% sure they'll have to be memorized.
- Tue Nov 13, 2018 2:41 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Trigonal Bypyramidal
- Replies: 1
- Views: 152
Re: Trigonal Bypyramidal
I believe there are five bonds around the central atom and three of them are along the equator with 120 degree angles and the other two are at the axis with 90 degree angles i'm pretty sure.
- Fri Nov 09, 2018 10:00 pm
- Forum: Resonance Structures
- Topic: Resonance with formal charge
- Replies: 6
- Views: 574
Re: Resonance with formal charge
So formal charge doesn't really have anything to do with resonance?
- Fri Nov 09, 2018 9:58 pm
- Forum: Lewis Structures
- Topic: Lewis Structure
- Replies: 10
- Views: 769
Re: Lewis Structure
Make sure the element with the lowest ionization energy is in the center.
- Fri Nov 09, 2018 9:56 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Naming the shape
- Replies: 6
- Views: 610
Re: Naming the shape
I believe there are 5: linear, trigonal-planar, tetrahedral, trigonal-bipyramidal, and octahedral.
- Tue Oct 30, 2018 7:29 pm
- Forum: Lewis Structures
- Topic: Drawing Lewis Structures
- Replies: 14
- Views: 1943
Re: Drawing Lewis Structures
Does resonance somehow affect the shape of structures?
- Tue Oct 30, 2018 7:28 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm Layout
- Replies: 3
- Views: 349
Re: Midterm Layout
Since the test covers fundamentals, quantum, and bonding I think it will be similar to our usual tests where it's mostly free response with some conceptual questions
- Tue Oct 30, 2018 7:24 pm
- Forum: Ionic & Covalent Bonds
- Topic: 3.19 6th edition
- Replies: 1
- Views: 474
3.19 6th edition
I know it says to emit c on this problem but how would you find how many unpaired electrons there are for this problem?
- Sun Oct 28, 2018 5:38 pm
- Forum: Properties of Electrons
- Topic: Coulomb
- Replies: 4
- Views: 638
Coulomb
Can someone please explain what coulombic attraction is
- Sun Oct 28, 2018 5:34 pm
- Forum: Ionic & Covalent Bonds
- Topic: the Octet rule
- Replies: 21
- Views: 3919
Re: the Octet rule
Wait what does hydrogen do in that situation?? Can you explain that better please
- Sun Oct 28, 2018 5:29 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Grading
- Replies: 3
- Views: 280
Re: Grading
I don't know the answer to 2 and 3 but you check your grades by going to the study list and then going to chemistry and then click on grades
- Sun Oct 21, 2018 3:26 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: shells
- Replies: 2
- Views: 306
shells
How do you correlate x, y, and z when there are more than three magnetic quantum numbers?
- Sun Oct 21, 2018 3:19 pm
- Forum: Properties of Electrons
- Topic: Test on Wednesday
- Replies: 3
- Views: 365
Test on Wednesday
Will tomorrow's lecture information be on Wednesday's test?
- Sun Oct 21, 2018 3:18 pm
- Forum: Properties of Electrons
- Topic: Wave Model
- Replies: 1
- Views: 217
Wave Model
Can someone pls explain how the wave model shows that electrons have quantized energy states
- Sat Oct 13, 2018 2:54 pm
- Forum: Properties of Light
- Topic: Frequency Equations
- Replies: 2
- Views: 138
Frequency Equations
I know some people were saying that there's an equation that combines E=(-hR)/(n^2) and E=hV. Does anyone know what it is?
- Sat Oct 13, 2018 2:52 pm
- Forum: Properties of Light
- Topic: light frequency
- Replies: 3
- Views: 144
light frequency
I know he went over this but I still don't get it. Why are there bigger spaces between certain quantum levels? Like the space between n=3 and n=2 is bigger than the space between n=4 and n=3.
- Sat Oct 13, 2018 2:43 pm
- Forum: Properties of Light
- Topic: Grades
- Replies: 2
- Views: 272
Re: Grades
We don't know until end of quarter.