Search found 117 matches
- Sun Mar 14, 2021 6:11 pm
- Forum: Administrative Questions and Class Announcements
- Topic: THANK YOU DR LAVELLE!
- Replies: 47
- Views: 6481
Re: THANK YOU DR LAVELLE!
ʅʕ•ᴥ•ʔʃ boost
- Fri Mar 12, 2021 7:18 pm
- Forum: Student Social/Study Group
- Topic: Playlist
- Replies: 86
- Views: 6351
Re: Playlist
Angelica Soriano 3L wrote:My favorite song at the moment is an anime opening but it's so good!!
Shogeki - Yuko Ando
https://open.spotify.com/track/5QwAdWCn ... zzNnCQbYsg
yessssss the ending for this season for aot is so amazing easily one of my favorite anime op/eds
- Thu Mar 11, 2021 4:14 pm
- Forum: General Rate Laws
- Topic: liquids and solids
- Replies: 6
- Views: 439
liquids and solids
Is there anything about not including liquids and solids in rate laws? Thanks!
- Sat Mar 06, 2021 5:49 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: E naught
- Replies: 8
- Views: 472
Re: E naught
E naught will be 0 when the cathode is the same metal as the anode. For example, if we were talking about Au and the oxidation was the same state for both the cathode and anode then E naught would be equal to 0
- Fri Mar 05, 2021 3:40 pm
- Forum: First Order Reactions
- Topic: Order Graphs
- Replies: 8
- Views: 445
Re: Order Graphs
As said that you might have to match graphs I would make sure how the reactions look with and without the natural log and for the different orders
- Mon Mar 01, 2021 3:06 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: TB 6.57
- Replies: 2
- Views: 175
Re: TB 6.57
So since it's not possible for us to automatically know the E o of HF we can calculate that value using the E o of fluorine from the appendix and the given E o for the whole reaction. So, the way we can start this off is +3.03V=2.87-E o . Here, we get that the unknown value is -.16V, which is the st...
- Fri Feb 26, 2021 6:52 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: sapling 6.57
- Replies: 1
- Views: 124
sapling 6.57
For 6.57 from the hw problems why do we square root the value K? I just want to confirm if my thought is correct that we have to square root K because it is Ka*Kb and the question is just asking for Ka since I got rusty on acids/bases
- Thu Feb 25, 2021 4:49 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Sapling 6N.3 part d
- Replies: 1
- Views: 143
Sapling 6N.3 part d
For part d in 6N.3 why is .55 being multiplied with .277 in the numberator in the solutions manual? I instead multiplied .55 with .867 in the denominator because of products over reactants (anode/cathode) as I thought .55 was part of the reactants and I checked the page that lists which problems hav...
- Tue Feb 23, 2021 3:38 pm
- Forum: Balancing Redox Reactions
- Topic: flipping reactions
- Replies: 5
- Views: 292
flipping reactions
When finding the half-reactions without a given cell diagram how do we know which reaction should be reversed when both equations have their electrons added on the same side?
- Tue Feb 23, 2021 12:42 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: cell potentials, K, and reduction
- Replies: 2
- Views: 211
cell potentials, K, and reduction
Could someone explain the relationship between positive/negative standard cell potentials, K, and reduction of H ions? I read that when the standard cell potential of a redox couple<0 then K<1, and that would cause hydrogen ions to be reduced. However I read a later statement that said "K>1 for...
- Mon Feb 22, 2021 2:30 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: table for potential difference [ENDORSED]
- Replies: 1
- Views: 164
table for potential difference [ENDORSED]
For Sapling problems where can I find the table for different potential differences? Like for section 6L values aren't given for voltages
- Mon Feb 22, 2021 2:04 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: sapling self test cell diagram
- Replies: 1
- Views: 147
sapling self test cell diagram
In the self test portion 6L.2A for Sapling where did the H2+(g) come from? I was able to get the rest except for that portion in the problem. Thank you!
- Mon Feb 22, 2021 1:55 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: mols in calculating gibbs free energy
- Replies: 5
- Views: 545
mols in calculating gibbs free energy
For finding the number of moles in the equation used to find the gibbs free energy I'm not super sure where it comes from so do the number of moles come from how many electrons are added to both the redox equations? From the problems that I've done so far the number of electrons added to both half r...
- Sat Feb 20, 2021 3:38 pm
- Forum: Balancing Redox Reactions
- Topic: Stoichiometric coefficients
- Replies: 3
- Views: 234
Re: Stoichiometric coefficients
As for balancing charges in redox equations I had to relearn oxidation numbers in case this is what you need so for example: MnO 4 - you want to know that O has a oxidation number of -2 and there are 4 Os. Therefore to find the oxidation number of Mn since it isn't clear as it's a transition metal y...
- Sat Feb 20, 2021 3:28 pm
- Forum: Student Social/Study Group
- Topic: Fave food
- Replies: 266
- Views: 29188
Re: Fave food
When I crave something spicy as a snack I definitely love eating tteokbokki! It's a korean dish made of rice cakes and fish cakes with spicy pepper sauce
- Sat Feb 20, 2021 3:25 pm
- Forum: Calculating Work of Expansion
- Topic: Work sign
- Replies: 46
- Views: 1936
Re: Work sign
When a problem says that compression occurs on a system I think of the work as positive as the surroundings are doing work on the system. So, when expansion occurs work would be negative since it's the system this time doing the work by expanding.
- Sat Feb 20, 2021 3:23 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Textbook 4F.17
- Replies: 4
- Views: 463
Re: Textbook 4F.17
In this question the book asks for the entropy of the whole process of water heating up, turning into vapor, and the water vapor cooling down to the 85 degrees. Realistically the process of the problem doesn't make sense since going below 100 degrees C would be liquid water instead of water vapor bu...
- Sat Feb 20, 2021 3:14 pm
- Forum: Student Social/Study Group
- Topic: Post Midterm 2 De-stressing
- Replies: 92
- Views: 6219
Re: Post Midterm 2 De-stressing
I destressed by catching up with shows like AOT and jujutsu kaisen last night n decided to sleep in until like 2 in the afternoon today :>
- Mon Feb 15, 2021 1:54 pm
- Forum: Student Social/Study Group
- Topic: Fav Shows of the Moment
- Replies: 115
- Views: 27868
Re: Fav Shows of the Moment
If you're into action/thriller anime I definitely recommend Parasyte on Netflix
- Sat Feb 13, 2021 6:04 pm
- Forum: Calculating Work of Expansion
- Topic: calculating irreversible work of any gas vs ideal isothermal gas
- Replies: 1
- Views: 226
calculating irreversible work of any gas vs ideal isothermal gas
Would calculating the irreversible work done by a gas vs an ideal isothermal gas be done differently? For example in Matthew's workshop (Q1 Week 6) a question asked to find the work done of an ideal gas in the isothermal reversible process while the initial pressure and volume and final volume was g...
- Fri Feb 12, 2021 4:55 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Sapling 4I.5
- Replies: 2
- Views: 184
Sapling 4I.5
In reference to the solutions manual for 4I.5 where did 75.3 J/K*mol come from towards the last couple lines of the calculation? I believe that's the Cp,m value of the temperature change equation of entropy but I'm unable to derive that exact value. Thanks!
- Wed Feb 10, 2021 4:32 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: gibbs self test 4J.1A
- Replies: 2
- Views: 180
gibbs self test 4J.1A
Can a nonspontaneous process with a negative ΔS become spontaneous if the temperature is increased (assuming that ΔH and ΔS are both independent of temperature)? answer: no
I'm having trouble understanding this question so could someone break it down on what it means? Thanks!
I'm having trouble understanding this question so could someone break it down on what it means? Thanks!
- Tue Feb 09, 2021 3:55 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: entropy change in surroundings formula
- Replies: 2
- Views: 223
entropy change in surroundings formula
When calculating the entropy change of surroundings I'm not sure when the equation should be negative. What are some of the conditions in order for the equation to be negative so that the resulting entropy change in surroundings is negative?
- Tue Feb 09, 2021 3:41 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Sapling 4I.1
- Replies: 1
- Views: 218
Sapling 4I.1
For #1 in 4I in the solutions manual why is 40000J positive in one of the calculations? Is it because the reservoir at 200K is gaining the 4000J that it is positive and the reservoir at 800K is having its heat energy transferred away therefore the 40000J is negative? Thanks!
- Mon Feb 08, 2021 1:34 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: michael nguyen week 5 problem
- Replies: 1
- Views: 198
michael nguyen week 5 problem
You have just discovered two mysterious gases: purple gas (PG) and brown gas (BG). They react to somehow produce water vapor and carbon dioxide via the reaction below. 2 PG(g) + BG(g) → 4 CO2(g) + H2O(g) ΔH = -245 kJ Determine the change in internal energy when 1.00 mol of CO2 is produced by the abo...
- Mon Feb 08, 2021 11:40 am
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: temp change irreversible reaction
- Replies: 4
- Views: 249
temp change irreversible reaction
Could someone explain how temperature change occurs with irreversible reactions? Thanks!
- Mon Feb 08, 2021 11:17 am
- Forum: Student Social/Study Group
- Topic: Book Recommendations
- Replies: 135
- Views: 12126
Re: Book Recommendations
I definitely recommend The Book Thief if you haven't read it yet! It centers on people during the holocaust and the writing depicts their narratives really well and it's one of the few books I wouldn't mind rereading anytime
- Sun Feb 07, 2021 4:14 pm
- Forum: Student Social/Study Group
- Topic: Review
- Replies: 5
- Views: 213
Re: Review
Before finals/midterms UA Justin holds a review session since his step-up and workshop are back to back so he just combines the hours
- Sat Feb 06, 2021 5:38 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: calculating standard entropy
- Replies: 1
- Views: 102
calculating standard entropy
Q: Calculate the standard entropy of vaporization of argon at its normal boiling point ΔH vap /(kJ*mol -1 ) for argon=6.5 and boiling point of argon is T b /K is 87.3; answer: 74 J/(K*mol) I used the equation of the stand entropy of vaporization to find the vaporization of argon and divided 87.3 fro...
- Thu Feb 04, 2021 5:56 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: enthalpy of vaporization
- Replies: 1
- Views: 97
enthalpy of vaporization
A sample of benzene, C 6 H 6 was brought to 80°C, its normal boiling point. The heating was continued until an additional 15.4 kJ had been supplied, resulting in 39.1 g of boiling benzene becoming vaporized. What is the enthalpy of vaporization of benzene at its boiling point? Answer: 30.8 kJ/mol Us...
- Thu Feb 04, 2021 5:07 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Adiabatic and Diathermic Walls
- Replies: 3
- Views: 231
Re: Adiabatic and Diathermic Walls
From last quarter's experience and from this one so far I don't think it's necessary to memorize those definitions since conceptual topics he talks about are definitely discussed at least for a little bit during lectures so I wouldn't worry about it in my opinion since he didn't mention it at all
- Thu Feb 04, 2021 5:03 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Sapling using ΔH and ΔU
- Replies: 4
- Views: 211
Sapling using ΔH and ΔU
Self-test 4C.1A In an exothermic reaction at constant pressure, 50. kJ of energy left the system as heat and 20. kJ of energy left the system as expansion work. What are the values of (a) ΔH and (b) ΔU for this process? Answers: -50 kJ; -70 kJ My question is why would only the 50 kJ be accounted for...
- Mon Feb 01, 2021 3:05 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Sapling 4A.9
- Replies: 2
- Views: 151
Sapling 4A.9
I'm having trouble understanding why the calculations were arranged as it was by looking at the manual for 4A.9. Specifically, I'm not sure why 100 degrees C was subtracted from the final temperature for copper and 22 subtracted from the final temperature of water. If anyone could explain the concep...
- Sat Jan 30, 2021 7:22 pm
- Forum: Student Social/Study Group
- Topic: Spring 2021
- Replies: 106
- Views: 12133
Re: Spring 2021
Personally I'm going to try to take it next quarter since I've heard it's easier online and especially because I think taking 14b and then lab back-to-back would be easier than waiting for a long period of time because I'm definitely going to forget a lot of what I learned this quarter if it's going...
- Sat Jan 30, 2021 3:39 pm
- Forum: Phase Changes & Related Calculations
- Topic: Endothermic v. Exothermic
- Replies: 139
- Views: 10540
Re: Endothermic v. Exothermic
Lorena_Morales_1K wrote:Why is bond formation exothermic again?
I believe it's exothermic because the system loses energy to form the bonds and since there's a decrease in energy, the energy is lost as heat and makes the process exothermic
- Sat Jan 30, 2021 3:37 pm
- Forum: Student Social/Study Group
- Topic: Go treat yourself after MT1!
- Replies: 75
- Views: 4257
Re: Go treat yourself after MT1!
Quinton Sprague 1A wrote:Any ideas when we should know our grades? Shouldn't expect any curve right?
Sadly I'd say to not expect a curve on exams for this class but from what happened last quarter we can maybe expect grades to be out around the end of next week since it took about a week for grades to return in 14a
- Sat Jan 30, 2021 3:32 pm
- Forum: Student Social/Study Group
- Topic: Go treat yourself after MT1!
- Replies: 75
- Views: 4257
Re: Go treat yourself after MT1!
Once I catch up with my other classes the past week I definitely plan on going outside for a little bit and practice skating or drive for a little bit! Being cooped up in the house studying for the midterm was really draining so getting fresh air is always a good thing
- Tue Jan 26, 2021 12:50 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: increasing base strength sapling
- Replies: 2
- Views: 169
increasing base strength sapling
For 6C.9 in Sapling I got the same exact pOHs that the solutions manual gave out and the question was to order the bases in increasing strength. The way I did it was 4.75<8.75<9.25<10.55 since I thought that the higher the number meant a stronger pOH. The answer however put the arrows in the opposit...
- Sun Jan 24, 2021 4:43 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Using mean bond enthalpies for enthalpy of a reaction
- Replies: 2
- Views: 154
Using mean bond enthalpies for enthalpy of a reaction
I was working through the example in 4E.3 for reference and my question is how would we know which bonds have to be broken in a substance, such as CH 3 CHBrCH 2 Br if the question doesn't tell us which ones? Also how necessary would drawing lewis structures in these type of problems be since Lavelle...
- Sun Jan 24, 2021 3:52 pm
- Forum: Student Social/Study Group
- Topic: Favorite Music
- Replies: 113
- Views: 9958
Re: Favorite Music
I really love R&B, alternative R&B and I'm also getting into K R&B so if anyone has recommendations pass them over lol. Some of the artists I love are SZA, Kehlani, Brockhampton, Tyler, DEAN, GOT7, Joji, and the list of course goes on. I'm excited to see other people's music tastes than...
- Sun Jan 24, 2021 3:46 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: How to find the H+ from pH
- Replies: 12
- Views: 470
Re: How to find the H+ form pH
For example if the pH was 4, you would do 10-4 to find the concentration!
- Sat Jan 23, 2021 7:46 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Calculating enthalpy of formation formulas
- Replies: 2
- Views: 195
Calculating enthalpy of formation formulas
I was working through a self test that Sapling gave right after 4D.6 and I have no clue on how to write the reaction formula so therefore I can't reach the solution since I'm not sure what chemicals will be produced in order to look up their values for their enthalpies of formation. Do we have to kn...
- Mon Jan 18, 2021 6:13 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Sapling 6.19
- Replies: 1
- Views: 183
Sapling 6.19
For parts a and b could someone explain the answers? After reading the solutions from the manual I'm still confused on the problem as I don't have a starting point on understanding it. Thanks for any help!
- Mon Jan 18, 2021 5:52 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Textbook Problems 6D
- Replies: 2
- Views: 183
Re: Textbook Problems 6D
Right above exercise one theres 2 links that lead to the equilibrium constants! I'm sure we don't have to memorize these values since that's really extensive
- Mon Jan 18, 2021 5:49 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Sapling 6D calculate pH
- Replies: 2
- Views: 214
Sapling 6D calculate pH
For questions 15, 17, and 19 in 6D how would we able to calculate pH? I wasn't able to find the equilibrium concentrations of those acids/bases on the tables it told us to refer to and I'm assuming we shouldn't have to google the concentrations, so are these chemicals conjugate acids/bases? For 6D.1...
- Thu Jan 14, 2021 5:43 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: sapling #4
- Replies: 4
- Views: 144
Re: sapling #4
At a certain temperature, the given reaction has an equilibrium constant of Kp=391 . PCl3(g)+Cl2(g)↽−−⇀PCl5(g) PCl5 is placed in a sealed container at an initial pressure of 0.0640 bar . What is the total pressure at equilibrium? Im having trouble getting the correct answer for this problem. I set ...
- Mon Jan 11, 2021 5:18 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Sapling 6A.19 part c)
- Replies: 2
- Views: 206
Sapling 6A.19 part c)
Calculate the molar concentration of OH - in solutions with the following molar concentration of H 3 O + : c) 3.1 mol/L I was able to get to get the other parts correct as I just divided what was given from 1x10 -14 but I ended up getting 3.2x10 -15 as my answer but the solution manual says 3.2 x 10...
- Mon Jan 11, 2021 11:11 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Sapling 5.57 b)
- Replies: 3
- Views: 218
Sapling 5.57 b)
Given that K = 6 x 10 3 , calculate the amount (in moles) of NO that must be added to a 1 L vessel containing .245 mol SO 3 to form .24 mol SO 2 at equilibrium. SO 3 (g)+NO(g) -> SO 2 (g)+NO 2 (g) I got confused on how to solve this problem and after looking at the solution manual why would we subtr...
- Mon Jan 11, 2021 10:54 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 5I.13
- Replies: 2
- Views: 90
Re: 5I.13
The way I discerned the two was whether the question asked for equilibrium or equilibrium *composition* so then I would look at Kc but correct me if I'm wrong on my reasoning
- Mon Jan 11, 2021 10:52 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Textbook problem 5.33
- Replies: 3
- Views: 146
Re: Textbook problem 5.33
Since the images are showing the states of equilibrium, only temperature can change the equilibrium concentration. Therefore, only a) would be the correct answer. For b), I believe it doesn't matter whether you add or remove atoms from a concentration, the equilibrium constant will be the same after...
- Mon Jan 11, 2021 10:34 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Sapling 5J.5 d)
- Replies: 3
- Views: 204
Sapling 5J.5 d)
For part d) in 5J.5: State whether reactants or products will be favored by an increase in the total pressure (resulting from compression) or if there is no change on the equilibria. 2HD(g) + H 2 (g) ⇌ D 2 (g) Originally my answer was that the products would be favored because there is 1 mole compar...
- Mon Jan 11, 2021 10:18 am
- Forum: Student Social/Study Group
- Topic: Comfort Movies
- Replies: 168
- Views: 22491
Re: Comfort Movies
If you like animated films a popular one is A Silent Voice and personally I really like In This Corner of the World as it covers darker topics really well
- Thu Jan 07, 2021 5:36 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Stability 5I.13 sapling
- Replies: 2
- Views: 175
Stability 5I.13 sapling
How do we find which one of two molecules is thermodynamically more stable relative to its atoms? For reference this comes from part c) in 5I.13 and I'm not sure what the specific statements are on how to find out which molecule is more stable in comparison to another one referring to equilibrium. T...
- Wed Jan 06, 2021 5:44 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: dobule arrows
- Replies: 6
- Views: 212
dobule arrows
I was doing the sample problems that Sapling works out and what does "<<" mean? For example, "make the approximation that x << 3.21 and 6.21, then solve the equilibrium expression for x."
- Tue Jan 05, 2021 1:12 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Textbook Question 5H1)
- Replies: 5
- Views: 362
Re: Textbook Question 5H1)
a) they switched the placements of the reactants/products so you would just take the inverse of K, so K in this problem would be 1/41 b) the given equation is the given equation in the problem but the coefficients are just divided by 2 so you would take the square root of 41 as your answer (~6.4). N...
- Tue Jan 05, 2021 1:00 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: adding chemical equations
- Replies: 2
- Views: 138
adding chemical equations
For #5 on the Sapling hw and 5H.3 in the textbook for reference, how would you add various chemical equations together to eventually reach a new one of those combinations? I'm assuming this is a fundamental skill that I have to brush up on so I'd appreciate any help!
- Tue Jan 05, 2021 12:52 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Will adding a solid reactant increase the amount of product?
- Replies: 6
- Views: 1223
Re: Will adding a solid reactant increase the amount of product?
From what I understand about the topic for now is that even though solids aren't included in the expression for finding the equilibrium I think it could increase the amount of product being formed if the equation given isn't balanced since even though solids/liquids aren't included in finding equili...
- Tue Jan 05, 2021 12:18 pm
- Forum: Student Social/Study Group
- Topic: Advice for someone who didn't take 14A with professor Lavelle
- Replies: 61
- Views: 2695
Re: Advice for someone who didn't take 14A with professor Lavelle
Like what people have said the UA sessions are extremely helpful and although Lavelle calls it an extra resource I kind of see it as necessary sometimes because some UAs are really good about going over problems you'd never expect to see Lavelle throw at you but possibly could since many of the prob...
- Tue Dec 15, 2020 9:20 pm
- Forum: Student Social/Study Group
- Topic: Plans for Relaxing After Finals
- Replies: 98
- Views: 11523
Re: Plans for Relaxing After Finals
I'm definitely going to be sleeping a lot and I'm going to plan on being outside of my house a lot more, like my backyard or whatnot, since I've needed all the time I have to study for finals and haven't gotten fresh air much ;/
- Tue Dec 15, 2020 9:18 pm
- Forum: Student Social/Study Group
- Topic: Anxiety
- Replies: 109
- Views: 6964
Re: Anxiety
Personally I find it relaxing when I talk to my close friends! So whenever I take breaks I talk with them because it offers a temporary relief from anxieties and it also helps me not spiral into only thinking about myself and what I can do/ can't do and being in the company of others keeps my perspe...
- Tue Dec 15, 2020 9:14 pm
- Forum: Student Social/Study Group
- Topic: Study music
- Replies: 59
- Views: 6093
Re: Study music
I tried pavloving myself to this one soundtrack (I forgot the name but it was an instrumental that was looped for an hour) so that I could be 100% focused during the hour because I work suuuuper slow and adding distractions too and it kind of worked o.o
- Tue Dec 15, 2020 9:11 pm
- Forum: Student Social/Study Group
- Topic: Winter Break Plans
- Replies: 45
- Views: 1952
Re: Winter Break Plans
I'm going to be painting my board once I get the materials and plan it and hopefully and I can finish it over break! Besides that I'm literally gonna snooze
- Thu Dec 10, 2020 6:40 pm
- Forum: Student Social/Study Group
- Topic: Katherine Estoque acids/bases review
- Replies: 1
- Views: 151
Katherine Estoque acids/bases review
By any chance has Katherine posted her slides on chem comm when she went over acids and bases? I'm trying to look for it but so far I haven't been able to find it and in case she hasn't I'd really appreciate it anyone doesn't mind sending their notes from the session!
- Tue Dec 08, 2020 9:58 pm
- Forum: Identifying Acidic & Basic Salts
- Topic: acidic/basic solution of salts
- Replies: 4
- Views: 191
acidic/basic solution of salts
Decide whether an aqueous solution of each of the following salts has a pH equal to, greater than, or less than 7: KF F - + H 2 O -> HF + OH - (greater than 7) How do we know that it's specifically potassium that's left out of the equation? I got confused as fluorine also has a single charge but as ...
- Tue Dec 08, 2020 8:52 pm
- Forum: Conjugate Acids & Bases
- Topic: Proton Transfer
- Replies: 3
- Views: 271
Proton Transfer
Write the chemical equations for the proton transfer equilibria of the following acids in aqueous solution and identify the conjugate acid–base pairs in each case: C 6 H 5 NH 3 + when this reacted with water the compound lost a proton to become -NH 2 at the end along with H 3 O + as a product. I tho...
- Mon Dec 07, 2020 12:59 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: neutralization reactions
- Replies: 5
- Views: 273
neutralization reactions
I'm still struggling with understanding acids/bases so for neutralization reactions would water only be a product if the reactants are a strong acid and strong base? I was doing the textbook problems and I didn't see H2O come up as a product as there weren't any strong acids as reactants in the form...
- Sun Dec 06, 2020 8:33 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Sapling Week 9 #4
- Replies: 5
- Views: 332
Re: Sapling Week 9 #4
I think that they pretty much mean the same thing as they both have the same roles, so I believe that we were just introduced to the term ligand when we specifically dove into the topic of coordination complexes and ligands would be a more appropriate term than lewis bases somehow
- Sun Dec 06, 2020 8:29 am
- Forum: Bronsted Acids & Bases
- Topic: Difference between Bronsted Acid and Lewis acid?
- Replies: 4
- Views: 156
Re: Difference between Bronsted Acid and Lewis acid?
I believe that they are generally the same thing and you can use either name to refer to something but a lewis acid would be anything that accepts electron pairs and a bronsted acid would be something that is a proton acceptor. For example BF3 would be a lewis acid because it doesn't have any electr...
- Fri Dec 04, 2020 8:41 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: linear same atoms?
- Replies: 6
- Views: 354
linear same atoms?
I just want to confirm that if for example you had to find the molecular geometry for I3- it would be linear because they're all iodines? I got 3 lone pairs for that and thought it would be bent but it was linear instead
- Thu Dec 03, 2020 7:12 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: how many orbitals in n=2
- Replies: 12
- Views: 9480
how many orbitals in n=2
I was reviewing past textbook problems and a question was: How many orbitals can have the following quantum numbers in an atom for n=2? and I said 5 but the solution is apparently 4. Why would it be 4?
- Wed Dec 02, 2020 5:52 pm
- Forum: Lewis Acids & Bases
- Topic: Sapling J.7 part b
- Replies: 1
- Views: 183
Sapling J.7 part b
question: Select an acid and a base for a neutralization reaction that results in the formation of zinc nitrite answer: Zn(OH)2+2HNO2 -> Zn(NO2)2+2H2O I was able to get the basic skeleton of this down but I wasn't able to get the full answer because I wasn't sure on how to do the subscripts. This wa...
- Sun Nov 29, 2020 8:50 pm
- Forum: Hybridization
- Topic: hybridization, but very simple
- Replies: 9
- Views: 585
Re: hybridization, but very simple
That's right! and if there's 3 regions of electron density it would be sp2 as such
- Sun Nov 29, 2020 8:45 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordination Number & Resonance Structures
- Replies: 2
- Views: 216
Re: Coordination Number & Resonance Structures
Correct me if I'm wrong ofc but I think those are different topics? Because for resonance structures I don't think there's necessarily a coordination number as they're just marked with the sum of the formal charges of the atoms but I believe that for coordination compounds the coordination number wo...
- Sun Nov 29, 2020 8:41 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration for Transition Metals
- Replies: 3
- Views: 374
Re: Electron Configuration for Transition Metals
For the electron configurations I just keep an eye out if the transition metal in the configuration has 4 or 9 electrons because then you def want to fill it to 5 or 10 electrons by taking away an electron from the s orbital and adding it to the d orbital. As for orbital diagrams it helps when I vis...
- Fri Nov 27, 2020 7:38 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Sapling 9C.9 part c
- Replies: 1
- Views: 112
Sapling 9C.9 part c
c) determine the coordination number of the metal ion in each of the following complexes: [PtCl2(en)2]2+
solution: 6 (en is bidentate)
I just want to confirm that the solution is 6 because its 2 bidentates (4) + 2 chlorines? (2)(2)+2=6?
solution: 6 (en is bidentate)
I just want to confirm that the solution is 6 because its 2 bidentates (4) + 2 chlorines? (2)(2)+2=6?
- Fri Nov 27, 2020 7:32 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Sapling 9C.5 part b
- Replies: 1
- Views: 161
Sapling 9C.5 part b
Question: If the ligand can be polydentate, give the maximum number of places on the ligand that can bind simultaneously to a single metal center (CO3(2-), carbonate) b) answer: CO3(2-) can bind to a metal through either 1 or 2 oxygen atoms. Therefore, it can be a mono or bidentate ligand. Could som...
- Thu Nov 26, 2020 7:23 pm
- Forum: Naming
- Topic: Sapling 9C.3A
- Replies: 2
- Views: 88
Sapling 9C.3A
For part a in the textbook for 9C.3 how were there 3 potassiums in the solution: K3[Cr(CN)6]? The question is to write the formula for potassium hexacyanidochromate(III). Thanks for any help!
- Sat Nov 21, 2020 10:06 pm
- Forum: Ionic & Covalent Bonds
- Topic: How to determine which molecule is more ionic?
- Replies: 11
- Views: 2459
Re: How to determine which molecule is more ionic?
Yeaaa this seems really iffy I would ask a TA or a UA about this question because I've seen multiple typos in the textbook and sometimes they don't always explain the answers in the manual if this question is one of those cases
- Sat Nov 21, 2020 10:01 pm
- Forum: Student Social/Study Group
- Topic: Grading Scale for Chem14A
- Replies: 29
- Views: 1454
Re: Grading Scale for Chem14A
I remember people saying that sometimes, it really depends, that Lavelle can give points back or such at the end depending on the majority of student performance I believe. I wouldn't count on it too much tho ToT
- Sat Nov 21, 2020 9:58 pm
- Forum: Student Social/Study Group
- Topic: Midterm 2
- Replies: 19
- Views: 939
Re: Midterm 2
I remember that Lavelle said to expect problems from the textbook on the midterm and for midterm one there was definitely a question from the book and that was one of the few that I didn't do so I'm sure that I missed that one haha :( but def go through all the textbook problems to familiarize yours...
- Fri Nov 20, 2020 8:51 pm
- Forum: Student Social/Study Group
- Topic: Study Tips for Final Exam
- Replies: 57
- Views: 2515
Re: Study Tips for Final Exam
I would go to UA or workshop sessions as much as possible! The UAs can be really helpful for refreshers and people who create their workshop sheets sometimes pull old test problems from other years as practice problems.
- Fri Nov 20, 2020 8:49 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Trends in Pi vs Sigma Bonds?
- Replies: 3
- Views: 132
Re: Trends in Pi vs Sigma Bonds?
I just read about it in the textbook and I don't believe there is? Since they depend on the number of bonds that form I wouldn't say that there's a trend or a significantly noticeable one in my opinion.
- Sun Nov 15, 2020 3:45 pm
- Forum: Student Social/Study Group
- Topic: Favorite TV shows
- Replies: 277
- Views: 34543
Re: Favorite TV shows
My all time favorite show is Bobs Burgers, it's animated but also witty. I also have recently gotten into Naruto. I know that sounds kinda whack but surprisingly its really good, and has an insane amount of episodes to you'll always have another episode to watch. I actually just spent almost 11 hou...
- Sun Nov 15, 2020 3:43 pm
- Forum: Student Social/Study Group
- Topic: Chemistry Among Us
- Replies: 43
- Views: 2077
Re: Chemistry Among Us
I would call out green -_-
- Fri Nov 13, 2020 8:42 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Sapling 1E 15d
- Replies: 1
- Views: 69
Re: Sapling 1E 15d
Wait never mind it said to omit this part of the problem my bad
- Fri Nov 13, 2020 8:40 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Sapling 1E 15d
- Replies: 1
- Views: 69
Sapling 1E 15d
The question says to find the element with the ground state configuration [Rn](7s^2)(6d^2) and it says that it is thorium. How would this be so since there isn't an f block mentioned in the question? I found a previous post on this but it didn't help too much and a ta said it wouldn't be something t...
- Fri Nov 13, 2020 8:03 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: 3d and 4s orbital
- Replies: 1
- Views: 89
3d and 4s orbital
So just to clarify 3d^5 and even 3d^10 will always have a lower energy than 4s^2?
- Mon Nov 09, 2020 10:48 am
- Forum: Lewis Structures
- Topic: Sapling 9
- Replies: 3
- Views: 110
Sapling 9
On the 2nd part of the question for #9 "Which of the lewis structures of the perchlorate ion are most plausible based on the experimental data" I got it incorrect but on the feedback it told me how to find the average bond length ClO4-. Is that relevant to answering the question? If so how...
- Sun Nov 08, 2020 2:24 pm
- Forum: Student Social/Study Group
- Topic: Favorite TV shows
- Replies: 277
- Views: 34543
Re: Favorite TV shows
This new show on crunchyroll started releasing episodes somewhat recently and it's called jujutsu kaisen! If you like action anime it has a lot of potential since it just started and it gained a lot of attention already and I think that it's worth the hype so far. I also just finished this one calle...
- Sun Nov 08, 2020 2:17 pm
- Forum: Student Social/Study Group
- Topic: Chemistry Among Us
- Replies: 43
- Views: 2077
Re: Chemistry Among Us
I'd go ahead and follow green
- Sun Nov 08, 2020 2:16 pm
- Forum: Properties of Light
- Topic: Study Advice
- Replies: 50
- Views: 2108
Re: Study Advice
I'd say the bookwork problems are the most relevant so far to the tests that Lavelle gives but the worksheets that the UA provides have been really helpful too and I use them to solidy my understanding or as a means of finding out what I need to study more
- Tue Nov 03, 2020 7:03 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Sapling 1E.23
- Replies: 3
- Views: 98
Sapling 1E.23
For Ga on this problem I got [Ar] (4s^2)(3d^10)(4p^1) but the answer in the book for this problem has the 3d and 4s switched to [Ar](3d^10)(4s^2)(4p^1). I followed the Aufbau principle so I just wanted to make sure if I missed anything while doing this problem since sometimes there are typos in the ...
- Tue Nov 03, 2020 6:45 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: valence electrons in d block
- Replies: 3
- Views: 104
valence electrons in d block
How do I find the number of valence electrons for the d-block? (especially for elements in higher periods) I still get confused about this and thanks for any help!
- Sat Oct 31, 2020 3:50 pm
- Forum: DeBroglie Equation
- Topic: sapling 2, 3, 4: #25
- Replies: 4
- Views: 278
Re: sapling 2, 3, 4: #25
I would use de Broglie's for this problem but only for the electron part because an electron has mass but a photon doesn't have mass. For the photon one, your first step would be to convert 2.2 μm into m since planck's constant had meters in it. So, after converting into m you would find the frequen...
- Sat Oct 31, 2020 3:44 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Sapling spectroscopy problem
- Replies: 2
- Views: 98
Re: Sapling spectroscopy problem
Just like what was said I would use rhydberg's equation to find the number of spectral lines. From the equation, it solves for v and then you would have to solve for wavelength after that. As for the final energy levels, I think of it as what is the largest range that nfinal could be, and nfinal can...
- Fri Oct 30, 2020 10:00 pm
- Forum: Photoelectric Effect
- Topic: Sapling using de broglie's
- Replies: 7
- Views: 331
Sapling using de broglie's
The average speed of a diatomic chlorine molecule at 25 ∘C is 323.9 m⋅s−1 . What is the average wavelength of a chlorine molecule at this temperature? Assume that the molecule acts as a single particle. On the feedback that I get after getting it wrong it says to convert the molar mass of a diatomic...
- Fri Oct 30, 2020 9:15 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: F-block
- Replies: 2
- Views: 87
F-block
For the f-block why do we go up to 14 instead of 15?
- Fri Oct 30, 2020 7:48 pm
- Forum: Properties of Electrons
- Topic: Practice Problem
- Replies: 3
- Views: 200
Re: Practice Problem
So in the first part of the problem, it mentions velocity so you can use that information to find the kinetic energy. You'd also need the mass of an election as well, so Ke = (1/2)(mass of an electron)(velocity)^2. Also, you are given the work function. Therefore, you can use the equation E = Ek (ki...
- Fri Oct 30, 2020 7:41 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Sapling number of orbitals
- Replies: 4
- Views: 184
Sapling number of orbitals
"How many orbitals can have the following quantum numbers in an atom: n=2" I still get a little confused on this topic sometimes and the answer for this was 4 orbitals. How would it be 4 orbitals? This is part c from 1D.23 on sapling
- Sun Oct 25, 2020 4:04 pm
- Forum: General Science Questions
- Topic: Lyman vs. Balmer Series
- Replies: 5
- Views: 319
Re: Lyman vs. Balmer Series
For me, I just memorized the specific numbers that go into the lyman and balmer series but I suppose a way you can think of it is that for the lymann series it can fall to a lower level, n =1, than the balmer series, n=2. So, I just correlated the lyman series being able to reach a lower level to ha...