Search found 95 matches
- Fri Mar 13, 2020 4:28 am
- Forum: Administrative Questions and Class Announcements
- Topic: "Open Book" Final?
- Replies: 30
- Views: 2274
Re: "Open Book" Final?
Open book is pretty every resource you can lay your hands on. I don't think he will be using Respondus or another program to record us while taking the exam, so I think textbook, notes, and other instructional notes are all fair game for "open book." Thank goodness, the thought of using r...
- Fri Mar 13, 2020 4:24 am
- Forum: Administrative Questions and Class Announcements
- Topic: Thursday and Friday Answer Keys
- Replies: 2
- Views: 387
Re: Thursday and Friday Answer Keys
Thank you! :)
- Fri Mar 13, 2020 4:23 am
- Forum: Administrative Questions and Class Announcements
- Topic: Final Topics
- Replies: 10
- Views: 899
Re: Final Topics
Cumulative but for sure be ready for what we recently learned in class as that will definitely get you some points and everything else is fair game :)
- Fri Mar 13, 2020 4:19 am
- Forum: Administrative Questions and Class Announcements
- Topic: How long do we have to complete the final?
- Replies: 1
- Views: 282
Re: How long do we have to complete the final?
I think what he meant for "time will not be an issue" is that you most likely won't need the full 4 hours to complete the 6 questions. If it is similar to my other exams, then once you start you have the full 4 hours of time and it automatically submits once your test time is over.
- Fri Mar 13, 2020 4:15 am
- Forum: Administrative Questions and Class Announcements
- Topic: Final
- Replies: 12
- Views: 868
Re: Final
In his email, he did mention that the test-run will be happening today to make sure everything goes smoothly. I also wonder if it'll be multiple choice or fill in the blank with your answer.
- Sun Mar 08, 2020 10:08 pm
- Forum: General Rate Laws
- Topic: units
- Replies: 12
- Views: 701
Re: units
I don't think K has units? thought it was unitless since its an EQ constant.
- Sun Mar 08, 2020 10:06 pm
- Forum: *Electrophiles
- Topic: final
- Replies: 7
- Views: 1916
Re: final
I feel like it'll be evenly spread out for the other topic but more focus on thermodynamics as we spent a lot of time on that. or if it itll be worth the most points. but as mentioned above review everything bit by bit, no cramming.
- Sun Mar 08, 2020 10:02 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Kelvin or Celsius?
- Replies: 86
- Views: 7005
Re: Kelvin or Celsius?
yup, as mentioned above, you would use Kelvin.
- Sun Mar 08, 2020 9:57 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Excellence in Chemistry Award!
- Replies: 27
- Views: 10291
Re: Excellence in Chemistry Award!
Congrats Rachana! Keep excelling! :D
- Sun Mar 08, 2020 9:56 pm
- Forum: Balancing Redox Reactions
- Topic: e- amount
- Replies: 9
- Views: 688
Re: e- amount
Yes, it believes it would be deemed incorrect because if the electrons are unbalanced that means the charges don't cancel out even though the compounds themselves are equal. Just multiply it to get the common multiple and you'll be good. :)
- Sun Mar 08, 2020 9:53 pm
- Forum: Student Social/Study Group
- Topic: Final Jitters
- Replies: 457
- Views: 495208
Re: Final Jitters
Exactly! Stressing out or cramming at the last minute is never a good idea. It'll only increase anxiety ;(
-I know it does for me.
-I know it does for me.
- Thu Feb 27, 2020 7:16 am
- Forum: Balancing Redox Reactions
- Topic: Oxidizing agent and Reducing Agent
- Replies: 4
- Views: 441
Re: Oxidizing agent and Reducing Agent
An element that is oxidized is a reducing agent, because the element loses electrons, and an element that is reduced is an oxidizing agent, because the element gains electrons.
- Thu Feb 27, 2020 7:13 am
- Forum: Balancing Redox Reactions
- Topic: balancing in acidic solutions
- Replies: 4
- Views: 425
Re: balancing in acidic solutions
For an acidic solution (which are much easier to undersand IMO) we'd use H+ to balance out the charges and OH- for redox reactions in a basic solution.
- Thu Feb 27, 2020 7:10 am
- Forum: Balancing Redox Reactions
- Topic: Coefficient consideration
- Replies: 4
- Views: 352
Re: Coefficient consideration
Yeah, I believe so, you'll have to multiply the coefficient with the charge to get the total charge for that one compound.
- Thu Feb 27, 2020 7:07 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Midterm question Q3B
- Replies: 3
- Views: 447
Re: Midterm question Q3B
I think it doesn't just have to do with the number of moles, but with which reaction will be the strongest and thus produce the largest temperature change. Since b. has the highest molarity in the smallest volume, it will react the most (I think this is because the particle density is really high, ...
- Thu Feb 27, 2020 7:05 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Midterm 3D
- Replies: 4
- Views: 462
Re: Midterm 3D
Because pH>pKa, the acid will mostly deprotonate. Since it deprotonates it will become the conjugate base, ChH3COO-. The conjugate base will have a net charge of -1. so was this question asking the charge of the conjugate base? I believe so, well as the above question mentioned it asked for the net...
- Sun Feb 23, 2020 9:13 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing redox
- Replies: 6
- Views: 558
Re: Balancing redox
Lara Kristine Bacasen 1L wrote:The problem should usually tell you if it is in an acidic (H+) or basic (OH-) solution.
That's what I was thinking?
- Sun Feb 23, 2020 9:11 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cathode vs Anode
- Replies: 11
- Views: 987
Re: Cathode vs Anode
Cathode is what is being reduced and the anode is what is being oxidized. Mind you these would be the half rxns for their corresponding part.
- Sun Feb 23, 2020 9:05 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing Redox Equations
- Replies: 7
- Views: 505
Re: Balancing Redox Equations
depends if the compound is gaining or losing electrons which you can identify by calculating the charge for each. Remember, LEO and GER :) Also Oxidizing agents and Reducting agents are not the compounds that are reduced or oxidized, but the ones that cause the oxidation or reduction for the other c...
- Sun Feb 23, 2020 8:57 pm
- Forum: Ideal Gases
- Topic: Conjugate acid and bases
- Replies: 7
- Views: 598
Re: Conjugate acid and bases
you have to look at the charges. Once you locate the acid on the left, the conj. base will be the compound without the + charge or no Hand vice versa.
- Sun Feb 23, 2020 8:55 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Test 2
- Replies: 5
- Views: 411
Re: Test 2
The second half of thermochemistry and then the following outline about electrochemistry.
- Sun Feb 16, 2020 8:13 pm
- Forum: Phase Changes & Related Calculations
- Topic: Phase changes
- Replies: 8
- Views: 733
Re: Phase changes
I feel like usually, the problem would tell us the type of system it is along with the changes that have occurred: Melting, boiling, vaporizing, etc.
- Sun Feb 16, 2020 8:06 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: isolated system
- Replies: 16
- Views: 957
Re: isolated system
Yes, I believe they would equal 0 as no work or heat can be transfered.
- Sun Feb 16, 2020 8:00 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Meaning of q=-w
- Replies: 14
- Views: 2426
Re: Meaning of q=-w
This usually means that its an isothermal reversible reaction and that the internal energy is 0.
Id also suggest watching the Organic chemistry tutor on youtube as he has videos on thermodynamics!
Id also suggest watching the Organic chemistry tutor on youtube as he has videos on thermodynamics!
- Sun Feb 16, 2020 7:51 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Constant Pressure and Volume
- Replies: 6
- Views: 469
Re: Constant Pressure and Volume
Alondra wrote:Constant pressure: for monatomic it’s 5R/2; for diatomic it’s 7R/2
Constant volume: for monatomic it’s 3R/2; for diatomic it’s 5R/2
I addition to this, Organic Chemistry tutor has an entire video dedicated to this topic.
- Sun Feb 16, 2020 7:49 pm
- Forum: Balancing Redox Reactions
- Topic: Memorizing charges
- Replies: 11
- Views: 802
Re: Memorizing charges
I think we would be expected to memorize the charges that appear most on the homework and any Lavelle includes during his lectures.
- Sun Feb 09, 2020 8:28 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Strong acids and bases as gases
- Replies: 4
- Views: 255
Re: Strong acids and bases as gases
I believe in terms of dissociating 100%, we've only learned it through an aqueous state... so no need to worry about that now :p
- Sun Feb 09, 2020 8:24 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: ICE BOX
- Replies: 27
- Views: 973
Re: ICE BOX
I would agree that 10^-3 would be the cut-off, but that margin is so close. 10^-4 or 10^-5 would be a safer option. If you do decide to neglect x at 10^-3 always check at the end if your answer is withing 5%.
- Sun Feb 09, 2020 8:21 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Weak acid/base
- Replies: 14
- Views: 732
Re: Weak acid/base
Honestly, I just try to memorize all the strong acids and bases(there aren't that many) also check if they dissociate completely. :)
- Sun Feb 09, 2020 8:18 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Volume decrease
- Replies: 7
- Views: 304
Re: Volume decrease
Maia_Jackson_2C wrote:The rule is that the reaction will favor the side with less moles of gas for a volume decrease, you didn't mention gases so maybe the moles you counted weren't for gases?
This. Little details like these are the real kickers. Hope you figured it out OP.
- Sun Feb 09, 2020 8:15 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gibbs Free Energy on midterm
- Replies: 5
- Views: 333
Re: Gibbs Free Energy on midterm
Yeah, I believe we do. Everything on the first page of the learning outcomes but not the second.
- Tue Jan 28, 2020 9:34 pm
- Forum: Phase Changes & Related Calculations
- Topic: steam at 100ºC burn worse
- Replies: 7
- Views: 974
Re: steam at 100ºC burn worse
As Ally Huang answered in another similar question, "At 100 degrees celsius, steam will produce a worse burn than boiling water because steam contains more heat energy than boiling water. It holds more energy than boiling water because it has the heat energy of boiling water and the heat energy...
- Tue Jan 28, 2020 9:28 pm
- Forum: Phase Changes & Related Calculations
- Topic: Why does steam cause burns?
- Replies: 29
- Views: 1403
Re: Why does steam cause burns?
Leila_4E wrote:This makes me really scared of steam now!
Hahah, still does a great job of relaxing the body during the quarter system!
- Tue Jan 28, 2020 9:24 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Test 2
- Replies: 7
- Views: 288
Re: Test 2
As everyone previously mentioned I think Test 2 only focuses on topics discussed after the midterm. (not cumulative)
- Tue Jan 28, 2020 9:21 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Homework sections
- Replies: 7
- Views: 360
Re: Homework sections
205405339 wrote:i would assume we are starting at 4A rn
I think so too because the reading introduces the calorimeter and heat capacity which we left off in class.
- Sun Jan 26, 2020 6:16 pm
- Forum: Ideal Gases
- Topic: R Constant
- Replies: 26
- Views: 1333
Re: R Constant
Depending on the units given, use the R constant that uses the same units in order for them to cancel and give the desired answer.
- Sun Jan 26, 2020 6:10 pm
- Forum: Ideal Gases
- Topic: PV=NRT
- Replies: 7
- Views: 322
Re: PV=NRT
Timmy Nguyen Dis 1I wrote:we do not need to know that
Thank goodness. I was about to say.
- Sun Jan 26, 2020 6:08 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: La Chatelier's Principle
- Replies: 8
- Views: 575
Re: La Chatelier's Principle
If you can, draw a quick scale. If you add products, the scale will tip right and in order to regain equilibrium, the system will move to the left and vice versa.
- Sun Jan 26, 2020 6:03 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: pH
- Replies: 7
- Views: 313
Re: pH
Prasanna Padmanabham 4I wrote:It really depends on what information you are given, I feel like for most problems this is how I've been dealing with it...
1) convert pKa to Ka
Ka = 10^(-pKa)
2) write Ka concentration out and figure out [H+]
3) plug into pH = -log [H+]
I like this, clear and not too wordy :)
- Thu Jan 23, 2020 6:22 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Quadratic Equation for [EQ]
- Replies: 1
- Views: 103
Quadratic Equation for [EQ]
How do you all input the quadratic equation into the calculator without messing up? Is there a method to this madness of parenthesis?! :(
- Thu Jan 16, 2020 7:12 am
- Forum: Ideal Gases
- Topic: Topics for Test 1
- Replies: 17
- Views: 777
Re: Topics for Test 1
805097738 wrote:The UA's said the material would cover up to this friday's class material so I would focus of the first two weeks of information. The lecture videos that Lavelle posted cover a lot of the information and have great practice problems!
I forgot about his lecture videos! Nice :)
- Thu Jan 16, 2020 7:11 am
- Forum: Ideal Gases
- Topic: Topics for Test 1
- Replies: 17
- Views: 777
Re: Topics for Test 1
I'm not sure if Lavelle would structure his exams as he did 14A, but his tests were wickedly based on the homework. So, if you understand every single homework problem (Even the long complex ones) you will do awesome) :)
- Thu Jan 16, 2020 7:07 am
- Forum: Ideal Gases
- Topic: R constant
- Replies: 6
- Views: 294
Re: R constant
Qiu Ya Wu 4I wrote:Lavelle gives you 4 different values for the R constant on his formula sheet during tests. Whichever one you use depends on the units given in the problem.
Do you know if the problems will mention directly which R constant to use?(Like a given)
- Thu Jan 16, 2020 7:05 am
- Forum: Ideal Gases
- Topic: bars vs atm
- Replies: 8
- Views: 318
Re: bars vs atm
The units will be different and I don't think Lavelle will not mention the type of pressure (bar or atm) used in the problem. Either way, just be sure to maintain the units so you don't get points deducted.
- Thu Jan 16, 2020 7:01 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Factors
- Replies: 7
- Views: 300
Re: Factors
Yes, if I'm not mistaken, I think Lavelle did mention that temp would be the only factor that changes the K eq.
- Wed Jan 08, 2020 6:10 pm
- Forum: Ideal Gases
- Topic: R constant in PV=nRT
- Replies: 9
- Views: 345
Re: R constant in PV=nRT
Most likely it will be R=8.314 J/(K*mol) as it will be cancelled out with T= Kelvin. Also it probably will be given in our constant sheet on exam days.
- Wed Jan 08, 2020 6:07 pm
- Forum: Ideal Gases
- Topic: Review Ideal Gases
- Replies: 6
- Views: 357
Re: Review Ideal Gases
Organic Chemistry Tutor! Great Youtube channel for chemistry help :)
- Wed Jan 08, 2020 5:59 pm
- Forum: Ideal Gases
- Topic: Gas Law
- Replies: 6
- Views: 279
Re: Gas Law
I believe Prof. Lavelle mentioned it in class today. The gas law allows you to relate Pressure and Volume to concentration. You are then able to convert between partial pressures and concentration of a reactant in a reaction. [Conc.]=P/(RT)
- Wed Jan 08, 2020 5:53 pm
- Forum: Ideal Gases
- Topic: K and Q
- Replies: 13
- Views: 418
Re: K and Q
From an earlier post, I learned that K is for a reaction that is at equilibria or the equilibrium constant. Q is calculated to determine where the reaction will proceed, Forward or Reverse since the rxn is not at equilibrium.
- Wed Jan 08, 2020 5:51 pm
- Forum: Ideal Gases
- Topic: Q and K
- Replies: 7
- Views: 322
Re: Q and K
K describes the reaction once it reaches equilibrium. Q is calculated the same way as K, but it is for the reaction at any point in time that is not equilibrium. You can find Q and compare it with K to determine which way the reaction will proceed. Hope this helps. This makes so much sense! Thank y...
- Fri Dec 06, 2019 11:13 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4104043
Re: Post All Chemistry Jokes Here
Why do chemists enjoy working with ammonia?
-Because it's pretty basic stuff.
-Because it's pretty basic stuff.
- Fri Nov 22, 2019 9:20 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: T-Shaped ??
- Replies: 9
- Views: 816
Re: T-Shaped ??
I found this VSEPR Summary chart very helpful :)
https://www.studocu.com/en-us/document/george-mason-university/physical-chemistry-lab-ii/summaries/vsepr-summary/3958564/view
https://www.studocu.com/en-us/document/george-mason-university/physical-chemistry-lab-ii/summaries/vsepr-summary/3958564/view
- Fri Nov 22, 2019 9:18 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR Bond Angles for Shapes with Lone Pairs
- Replies: 5
- Views: 422
Re: VSEPR Bond Angles for Shapes with Lone Pairs
Mhm Looks good
- Fri Nov 22, 2019 9:15 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: Hydrogen Bonding Atoms
- Replies: 6
- Views: 353
Re: Hydrogen Bonding Atoms
I believe it does not matter whether they are bonded or not. Since its an intermolecular interaction H bond will be able to pair with any NOF atom.
- Fri Nov 22, 2019 9:13 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: 2E.5
- Replies: 5
- Views: 493
Re: 2E.5
It depends on the amount of lone pairs the central atoms has. This chart was helpful for me when trying to memorize them. Hopefully it appears. https://www.studocu.com/en-us/document/george-mason-university/physical-chemistry-lab-ii/summaries/vsepr-summary/3958564/view
- Thu Nov 21, 2019 4:20 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Test 2
- Replies: 14
- Views: 828
Re: Test 2
Kristina Rizo 3K wrote:I know the bonds (sigma and pi), molecular shapes, bond angles and the intermolecular forces will be on test 2. I'm not sure if that is all though.
Do you know if we will be expected to memorize the bond angles?
I thought he mentioned in lecture that we weren't but maybe I didn't listen correctly.
- Thu Nov 21, 2019 3:29 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Test 2
- Replies: 14
- Views: 828
Test 2
Can someone provide some important concepts to keep in mind for test 2? I have the memory of a goldfish and I really want to do well on this test. Thank you!
- Thu Nov 21, 2019 3:17 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: test 2
- Replies: 3
- Views: 338
Re: test 2
Megan Ngai- 3B wrote:^ retweet
re-retweet
- Thu Nov 21, 2019 3:16 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Test 2
- Replies: 7
- Views: 602
Re: Test 2
I think you can just say "bent" no matter if it is AX2E or AX2E2, but if asked to specify the electron geometry, you should state that it is trigonal planar for AX2E and tetrahedral for AX2E2. Hope this answer helps! Do you think we can specify all the names (Trigonal planar and tetrahedr...
- Thu Nov 21, 2019 3:12 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Name confusion
- Replies: 4
- Views: 308
Re: Name confusion
Like those above me mentioned, it all depends on the amount of lone pairs and bonded pairs to the atom. Tetrahedral doesn't have any lone pairs, whereas the see-saw molecular shape does. :)
- Sun Nov 17, 2019 7:46 pm
- Forum: Ionic & Covalent Bonds
- Topic: Electronegativity
- Replies: 7
- Views: 490
Re: Electronegativity
In case we aren't given it, it is best to know the trends from the periodic table. As we are given the Periodic table, just draw the trends directly on there for easy access.
- Sun Nov 17, 2019 7:38 pm
- Forum: Ionic & Covalent Bonds
- Topic: Strength and Length
- Replies: 18
- Views: 988
Re: Strength and Length
Longer Bond=Weaker bond
Shorter Bond= Stronger bond
:)
Shorter Bond= Stronger bond
:)
- Sun Nov 17, 2019 7:34 pm
- Forum: Ionic & Covalent Bonds
- Topic: Dipole-Dipole Interactions
- Replies: 3
- Views: 264
Re: Dipole-Dipole Interactions
April Meza 3K wrote:Here is an example of a dipole-dipole moment.
Thank you for providing a Visual. :) It is very helpful
- Sun Nov 17, 2019 7:34 pm
- Forum: Ionic & Covalent Bonds
- Topic: Hydrogen Bonds
- Replies: 6
- Views: 421
Re: Hydrogen Bonds
So only 3 elements can partake in hydrogen bonding: Oxygen, Nitrogen, and Flourine.
- Sun Nov 17, 2019 7:31 pm
- Forum: Ionic & Covalent Bonds
- Topic: London Dispersion
- Replies: 13
- Views: 732
Re: London Dispersion
Ah this one is the easiest :) From my understanding, all molecules will have London dispersion as an intermolecular force.
- Mon Nov 11, 2019 6:00 am
- Forum: Bond Lengths & Energies
- Topic: Size
- Replies: 13
- Views: 859
Re: Size
Does bond length also affect how strong the bond is? As Serena Siddiq said "The larger the radius of the atoms, the farther each of their centers are apart, and therefore, [they have a longer and weaker bond length than smaller radius atoms]. The smaller the radius of the atoms, the closer the...
- Mon Nov 11, 2019 5:56 am
- Forum: Dipole Moments
- Topic: Hydrogen bonds
- Replies: 17
- Views: 879
Re: Hydrogen bonds
From my understanding just those 3
- Tue Nov 05, 2019 6:36 pm
- Forum: Properties of Light
- Topic: Midterm formulas
- Replies: 6
- Views: 505
Re: Midterm formulas
yes ma'am :)
- Tue Nov 05, 2019 4:54 pm
- Forum: DeBroglie Equation
- Topic: Midterm Practice 4B
- Replies: 2
- Views: 216
Re: Midterm Practice 4B
So first you have to use De Broglie's equation to solve for velocity since you can't just use the speed of light equation because the wavelength given is for an electron and not light. Then you would just use the photoelectric effect equation and plug in the values for work function and kinetic ene...
- Tue Nov 05, 2019 2:20 pm
- Forum: DeBroglie Equation
- Topic: Midterm Practice 4B
- Replies: 2
- Views: 216
Midterm Practice 4B
8. b) A newly designed laser pointer with a certain frequency is pointed at a sodium metal surface. An electron is ejected from the metal surface with wavelength of 1.10 nm. What is the frequency of the light from the laser pointer? The work function of sodium is 150.6 kJ∙mol-1. I am getting lost on...
- Sun Nov 03, 2019 7:43 pm
- Forum: Electronegativity
- Topic: electronegativity trend
- Replies: 9
- Views: 745
Re: electronegativity trend
The larger the shell gets the lower electronegativity the element will have because that larger outer shell's electron is a lot farther from the nucleus.
- Sun Nov 03, 2019 7:39 pm
- Forum: Electronegativity
- Topic: Identifying the central atom
- Replies: 3
- Views: 184
Re: Identifying the central atom
Yuri Lin 4H wrote:I think the rule of thumb is that the central atom is the least electronegative atom, not the one with the lowest ionization energy, though I might be wrong. Nitrogen has a lower electronegativity than oxygen, so it would be the central atom.
Thank you! I too was puzzled.
- Sun Nov 03, 2019 7:26 pm
- Forum: Octet Exceptions
- Topic: Radical
- Replies: 6
- Views: 340
Re: Radical
Basically they are highly reactive because they are desperately trying to gain a complete octet, so theyd try to grab it from anywhere.
- Sun Nov 03, 2019 7:24 pm
- Forum: Lewis Structures
- Topic: Drawing Lewis Structures
- Replies: 5
- Views: 248
Re: Drawing Lewis Structures
When you draw a lewis structure you have to pay special attention to the valence electrons in each atom; they help determine if there are single/double/triple bonds. There is normally a center atom, and that is normally the atom that has the lowest ionization energy. For bonds (when the molecule is...
- Sun Nov 03, 2019 7:21 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Bruincast
- Replies: 4
- Views: 320
Re: Bruincast
I've also looked into that but came back empty. :( As the others have said we only have the Video modules that show us past lectures of very similar (if not the same) problems from class itself.
- Sun Oct 27, 2019 8:27 pm
- Forum: Ideal Gases
- Topic: Reading the textbook
- Replies: 262
- Views: 162942
Re: Reading the textbook
I've definitely have been in your shoes before. If the reading feels a intimidating, you should watch some youtube videos first about the concept so you won't go in blind. After that, as you go back to the reading it will feel more familiar and less intimidating!
- Sun Oct 27, 2019 8:22 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Advice from a Medical Student [ENDORSED]
- Replies: 297
- Views: 505642
Re: Advice from a Medical Student [ENDORSED]
Thank you so much! This was quite insightful
- Sun Oct 27, 2019 2:54 pm
- Forum: Lewis Structures
- Topic: Drawing the structure
- Replies: 7
- Views: 443
Re: Drawing the structure
Just be sure to know which elements are able to expand their octet so it doesn't mess up your lewis structure or cause confusion.
- Sun Oct 27, 2019 2:50 pm
- Forum: Lewis Structures
- Topic: Anion/Cations
- Replies: 2
- Views: 154
Re: Anion/Cations
Adding on to what the post above me said, I believe Usually it is denoted by brackets and then the charge is placed at the top right corner. If it has a 2+ charge then its be a cation and vice versa.
- Sun Oct 20, 2019 8:45 pm
- Forum: Photoelectric Effect
- Topic: Speed of Light
- Replies: 29
- Views: 1705
Re: Speed of Light
Yes, it is a constant. Some prefer to write it as 3.00x10^8 or 2.998x10^8 believe it or not sometimes, depending on which one you use, it can change your answer slightly. So for accuracy try to use the 2.998x10^8. Then your final answer should be in the appropriate Sig figs :)
- Sun Oct 20, 2019 8:40 pm
- Forum: Student Social/Study Group
- Topic: Final Jitters
- Replies: 457
- Views: 495208
Re: Final Jitters
I try to prepare myself as much as possible, and try to get some sleep! Sleep is super important, or try to get little naps here and there so you don't feel like you're lacking.
(lord knows anxiety is a sleep killer).
(lord knows anxiety is a sleep killer).
- Sun Oct 20, 2019 8:34 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Test 1 [ENDORSED]
- Replies: 107
- Views: 36018
Re: Test 1 [ENDORSED]
I can't find my test grades on ccle, where do I go? I had the same problem, you should try to check your discussion section or go talk to your discussion TA if that doesn't work. I thought TA's were supposed to give our tests back, but the score itself isn't necessarily the grade we got because of ...
- Wed Oct 16, 2019 12:31 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Question regarding definition of molecules
- Replies: 5
- Views: 600
Re: Question regarding definition of molecules
From my understanding, Avogadro's Number can be used to find Atoms, Molecules and Formula units of a compound. :)
- Wed Oct 16, 2019 12:28 pm
- Forum: SI Units, Unit Conversions
- Topic: Chemistry Grades
- Replies: 4
- Views: 284
Re: Chemistry Grades
As everyone else had mentioned, my TA also has only inputted homework assignments so far. Hopefully soon though!
- Fri Oct 11, 2019 9:58 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4104043
Re: Chemistry Jokes
If H20 is water, what is H204? Drinking, bathing, washing, swimming, etc. If H2O is the formula for water, what is the formula for ice? H2O cubed. Anyone know any jokes about the element sodium? Na. Have been trying to figure out the first joke for almost a year and I can't figure out lmao Hahah it...
- Fri Oct 11, 2019 9:53 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4104043
Re: Chemistry Jokes
Shreyesi Srivastava 2D wrote:Do you have 11 protons?
Cause you sodium fine
How have I never heard this one! HAHAh! :')
- Fri Oct 11, 2019 9:46 am
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Wrong Textbook
- Replies: 12
- Views: 1384
Re: Wrong Textbook
I have the 7th edition PDF if you want to use that one. I know some prefer the physical book, but that's expensive. Send me a Pm if you're interested, I'll gladly share it :)
- Fri Oct 11, 2019 9:27 am
- Forum: Balancing Chemical Reactions
- Topic: Balancing Chemical Reactions
- Replies: 20
- Views: 1245
Re: Balancing Chemical Reactions
Jarrett Peyrefitte 1L wrote:Try to make a list of reactants and products with their respective number of molecules and balance it one by one.
Yes! This simple list helps with confusion and knowing how much of what is on each side. I highly recommend this. :)
- Fri Oct 11, 2019 9:23 am
- Forum: Administrative Questions and Class Announcements
- Topic: Saying Thank You to Dr. Lavelle
- Replies: 490
- Views: 714046
Re: Saying Thank You to Dr. Lavelle
Speaking as someone who has taken 14A before and didn't do so well, Dr. Lavelle you really make these concepts so interesting and easy to understand. Your passion seeps through every lecture making your students feel as passionate to learn as you are to teach! Truly a one-of-a-kind professor :)
- Fri Oct 11, 2019 9:19 am
- Forum: Administrative Questions and Class Announcements
- Topic: Advice from a Medical Student [ENDORSED]
- Replies: 297
- Views: 505642
Re: Advice from a Medical Student [ENDORSED]
Wow, this is very helpful. Thank you :)
- Fri Oct 11, 2019 9:17 am
- Forum: Limiting Reactant Calculations
- Topic: Showing Work for Limiting Reactant Calculations on Tests [ENDORSED]
- Replies: 68
- Views: 7829
Re: Showing Work for Limiting Reactant Calculations on Tests [ENDORSED]
I think it would be best to show your work how you learned it rather than confusing yourself by adding minor steps. However, the minor steps might help you receive partial credit if your answer is incorrect. :)
- Thu Oct 03, 2019 7:23 pm
- Forum: Balancing Chemical Reactions
- Topic: Understanding how to get whole #s [ENDORSED]
- Replies: 18
- Views: 1404
Re: Understanding how to get whole #s [ENDORSED]
From what I've been reading on the forums, our final answer should always be in the correct number of significant figures in order to be concise. So if the fewest number of sig figs in the problem was 4 then your final answer should contain only 4 sig figs.
- Thu Oct 03, 2019 7:19 pm
- Forum: Significant Figures
- Topic: Sig Figs
- Replies: 6
- Views: 395
Re: Sig Figs
Can we round to the least amount of sig figs that are allowed for each step in our calculation? So basically round at each calculation to 2,3 sig figs?
- Thu Oct 03, 2019 7:13 pm
- Forum: SI Units, Unit Conversions
- Topic: Formula Names
- Replies: 7
- Views: 465
Re: Formula Names
I would agree with everyone else, prefixes and suffixes are important to remember as it will also help you write out formula names given only the chemical formula. I'm pretty sure they'll give us a list of chemicals they'd want us to remember for the exam and maybe try to write the names of others i...
- Thu Oct 03, 2019 7:01 pm
- Forum: SI Units, Unit Conversions
- Topic: mol, g.mol and g.mol-1
- Replies: 12
- Views: 1140
Re: mol, g.mol and g.mol-1
From what I've seen so far, grams/mole is equal to g.mol-1. Lavelle prefers us to write it as the latter since it makes canceling units simpler. I haven't seen g.mols though, so I wouldn't be able to explain the difference.