Search found 110 matches
- Mon Mar 15, 2021 11:25 am
- Forum: General Science Questions
- Topic: Final thoughts
- Replies: 28
- Views: 4465
Re: Final thoughts
It was definitely easier than expected especially since I finished with a lot of time to review my answers, however I do feel like some of the questions were worded slightly interesting. There was also a lot more elaborate problems than those in the textbook in my opinion.
- Mon Mar 15, 2021 11:23 am
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Is electromotive force the same as Ecellnaught?
- Replies: 3
- Views: 533
Re: Is electromotive force the same as Ecellnaught?
The standard EMF is equal to E naught of the cell. Hopefully this helps!
- Mon Mar 15, 2021 11:22 am
- Forum: Administrative Questions and Class Announcements
- Topic: Final jitters
- Replies: 8
- Views: 725
Re: Final jitters
Hi, I saw this after the final but I hope your final went great and you didn't over stress yourself too much. I know how hard it can be when all you can think about is preparing more for finals especially when you have multiple within the same week. At least it's all over!!!
- Mon Mar 15, 2021 10:59 am
- Forum: Administrative Questions and Class Announcements
- Topic: THANK YOU DR LAVELLE!
- Replies: 47
- Views: 6260
Re: THANK YOU DR LAVELLE!
b o o s t !!!
Thank you for an awesome first two quarters at UCLA Dr. Lavelle, we really appreciate all the time and effort you put in this class for us :)
Thank you for an awesome first two quarters at UCLA Dr. Lavelle, we really appreciate all the time and effort you put in this class for us :)
- Mon Mar 15, 2021 10:58 am
- Forum: Student Social/Study Group
- Topic: Spring Break
- Replies: 53
- Views: 3154
Re: Spring Break
I'm planning on redoing my room! Doing school in my room all day has made it feel more boring and less exciting to come in here so I'm planning on changing it up a bit.
- Mon Mar 15, 2021 1:33 am
- Forum: *Enzyme Kinetics
- Topic: intermediates vs. catalysts
- Replies: 31
- Views: 1286
Re: intermediates vs. catalysts
Intermediates are produced then consumed, while catalysts are present as "reactants" and then produced.
- Mon Mar 15, 2021 1:32 am
- Forum: Student Social/Study Group
- Topic: Plans for Summer/school year
- Replies: 34
- Views: 1465
Re: Plans for Summer/school year
Aw, it's so nice of you to ask! I think I'll be devoting my summer to hopefully some local travel, two summer classes, and a job.
- Mon Mar 15, 2021 1:30 am
- Forum: Zero Order Reactions
- Topic: Overall order of the reaction
- Replies: 45
- Views: 1734
Re: Overall order of the reaction
The overall order of the reaction can be determined by adding the individual orders together.
- Mon Mar 15, 2021 1:30 am
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: What was your favorite chem topic?
- Replies: 137
- Views: 8555
Re: What was your favorite chem topic?
To be honest, I really enjoyed kinetics. I wish we got to spend more time on it.
- Mon Mar 15, 2021 1:29 am
- Forum: Student Social/Study Group
- Topic: On Campus class vs. remote
- Replies: 21
- Views: 1280
Re: On Campus class vs. remote
I think we won't know until a while from now. All we can do is hope for the best!
- Mon Mar 15, 2021 1:28 am
- Forum: Administrative Questions and Class Announcements
- Topic: Final Grades
- Replies: 19
- Views: 1348
Re: Final Grades
I think we will have our final grades before we go for spring break!
- Sat Mar 06, 2021 12:09 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Video Review
- Replies: 8
- Views: 477
Re: Video Review
Honestly, the Organic Chemistry Tutor is a really good resource to use, especially is you want to study a particular area more.
- Sat Mar 06, 2021 12:07 pm
- Forum: Student Social/Study Group
- Topic: Note Taking
- Replies: 145
- Views: 15059
Re: Note Taking
I personally hand-write my notes as I watch the lecture. I review them the week before the midterms and do the textbook problems.
- Sat Mar 06, 2021 12:03 pm
- Forum: Student Social/Study Group
- Topic: Chem 14C
- Replies: 17
- Views: 853
Re: Chem 14C
Hi! I have heard that it really just depends on the person. People that absolutely hate gen-chem tend to think the o-chem is easier. Personally, I really liked gen-chem though so I really don't know what to expect.
- Sat Mar 06, 2021 12:01 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: E is State Function or no?
- Replies: 3
- Views: 207
Re: E is State Function or no?
E is not a state function as it does depend on the path taken.
- Sat Mar 06, 2021 12:00 pm
- Forum: Student Social/Study Group
- Topic: 14B Final
- Replies: 22
- Views: 952
Re: 14B Final
In Chem 14A, he allotted the portion of the final to the amount of time we spent covering the material in lecture, so my guess is he would do the same this quarter.
- Sat Feb 27, 2021 10:50 am
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Gibbs Free Energy Equation and n
- Replies: 13
- Views: 569
Re: Gibbs Free Energy Equation and n
n is representative of the moles of e-s transferred.
- Sat Feb 27, 2021 10:49 am
- Forum: Balancing Redox Reactions
- Topic: Determining which molecule is the oxidizing agent
- Replies: 49
- Views: 1753
Re: Determining which molecule is the oxidizing agent
Yes, the oxidizing agent is the substance that is being reduced, and vice versa is true. The reducing agent is the substance being oxidized.
- Sat Feb 27, 2021 10:47 am
- Forum: Balancing Redox Reactions
- Topic: Adding OH-
- Replies: 5
- Views: 347
Re: Adding OH-
You should add H20 and OH- to balance reactions in basic solutions. It will usually tell you in the problem if it's acidic or basic.
- Sat Feb 27, 2021 10:44 am
- Forum: Balancing Redox Reactions
- Topic: Acidic vs. Basic
- Replies: 20
- Views: 750
Re: Acidic vs. Basic
In acidic solutions, you're supposed to use H+ and H2O to balance the equation while in basic solutions, you have to use OH-and H2O.
- Sun Feb 21, 2021 10:05 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Adiabatic
- Replies: 26
- Views: 1064
Re: Adiabatic
Adiabatic means the q=0 for the system. No heat energy can enter or leave the system.
- Sun Feb 21, 2021 10:04 pm
- Forum: Student Social/Study Group
- Topic: Classes for next quarter?
- Replies: 165
- Views: 13024
Re: Classes for next quarter?
I'm planning on taking chem 14c and LS 7A!
- Sun Feb 21, 2021 10:01 pm
- Forum: Student Social/Study Group
- Topic: Points needed to pass?
- Replies: 76
- Views: 6632
Re: Points needed to pass?
According to the syllabus, a 50% or higher is needed to pass the class.
- Sun Feb 21, 2021 10:00 pm
- Forum: Student Social/Study Group
- Topic: Fave food
- Replies: 266
- Views: 28550
Re: Fave food
Honestly white chocolate covered strawberries are a favorite right now.
- Sun Feb 21, 2021 9:58 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Isolated System
- Replies: 11
- Views: 717
Re: Isolated System
I'm not sure it is completely possible but I think the best bet would be in a vacuum.
- Sun Feb 21, 2021 9:57 pm
- Forum: Student Social/Study Group
- Topic: We made it through Midterm 2!
- Replies: 71
- Views: 3502
Re: We made it through Midterm 2!
It feels so good. Honestly thankful fo rthe exam because it will make the review for the final a lot easier.
- Sun Feb 21, 2021 9:55 pm
- Forum: General Science Questions
- Topic: Chem Jokes
- Replies: 28
- Views: 1536
Re: Chem Jokes
I don't trust atoms, I heard they make everything up.
- Sun Feb 21, 2021 9:53 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Can We Review our Exams?
- Replies: 69
- Views: 2930
- Sun Feb 21, 2021 9:52 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2985835
Re: Post All Chemistry Jokes Here
I would but all the good ones Argon.
- Sat Feb 13, 2021 1:35 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Kelvin conversion
- Replies: 40
- Views: 2858
Re: Kelvin conversion
Add either 273.15 or 273 to your degrees celsius to convert to Kelvin.
- Sat Feb 13, 2021 1:34 pm
- Forum: Student Social/Study Group
- Topic: Thoughts on Upcoming Midterm 2
- Replies: 41
- Views: 1581
Re: Thoughts on Upcoming Midterm 2
Honestly, I'm feeling a little uneasy about this midterm because the content is more difficult compared to what we have done in the past. However, I'm sure that if you're putting in the time and effort to review the notes and do the textbook problems that you will do just fine!
- Sat Feb 13, 2021 1:32 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Difference between ΔS° and ΔS
- Replies: 9
- Views: 2611
Re: Difference between ΔS° and ΔS
The one with the degree symbol indicates that it is the entropy value at equilibrium. Hope this helps!
- Sat Feb 13, 2021 1:31 pm
- Forum: Ideal Gases
- Topic: Units for K
- Replies: 29
- Views: 1121
Re: Units for K
Since K is a ratio where all units cancel out, there are none.
- Sat Feb 13, 2021 1:31 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Is it necessary to memorize Cp,m or Cv,m values? [ENDORSED]
- Replies: 26
- Views: 1172
Re: Is it necessary to memorize Cp,m or Cv,m values? [ENDORSED]
These values are given to us on the equation sheet we can use on the test so I don't think you need to memorize them although it never hurts to!
- Sun Feb 07, 2021 7:27 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Combustion = Exothermic
- Replies: 23
- Views: 791
Re: Combustion = Exothermic
The energy that is released from forming the bonds in the products is greater than the energy used to break the bonds in the reactants.
- Sun Feb 07, 2021 7:26 pm
- Forum: Student Social/Study Group
- Topic: Superbowl
- Replies: 10
- Views: 536
Re: Superbowl
Definitely thought that Buccs were gonna win anyway. Wish the game could have been closer tho.
- Sun Feb 07, 2021 7:25 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Can We Review our Exams?
- Replies: 69
- Views: 2930
Re: Can We Review our Exams?
I think you can ask your TA and they can help you go over it one on one.
- Sun Feb 07, 2021 7:20 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm 2
- Replies: 33
- Views: 1948
Re: Midterm 2
I don't believe we know how far we are going to get to by midterm 2 so far.
- Sun Feb 07, 2021 7:18 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Heat in isothermal expansion
- Replies: 5
- Views: 136
Re: Heat in isothermal expansion
An example of where when heat is being added, it is actually being used to break the bonds and used as energy instead of an addition to the temperature.
- Sun Jan 31, 2021 2:41 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: is HClO3 weak or strong? [ENDORSED]
- Replies: 49
- Views: 3969
Re: is HClO3 weak or strong? [ENDORSED]
I believe that HClO3 is a strong acid. Hope this helps!
- Sun Jan 31, 2021 2:40 pm
- Forum: Phase Changes & Related Calculations
- Topic: when to assume x is insignificant
- Replies: 86
- Views: 6386
Re: when to assume x is insignificant
Dr. Lavelle said to check and see if the ionization percentages are less than 5% but also if the K is less than 10^-3, then you can approximate.
- Sun Jan 31, 2021 2:35 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Neutralization
- Replies: 25
- Views: 981
Re: Neutralization
A base and acid form a salt and water as the products, which results in a neutral pH of usually 7.
- Sun Jan 31, 2021 2:32 pm
- Forum: Student Social/Study Group
- Topic: Worried About MT 1 Grades
- Replies: 39
- Views: 1628
Re: Worried About MT 1 Grades
I definitely agree with where you're coming from. Midterm 1 last quarter was definitely easier than midterm 1 this quarter. Doing the textbook problems really helps so I recommend heavily studying those for the upcoming midterms :)
- Sun Jan 31, 2021 2:27 pm
- Forum: Administrative Questions and Class Announcements
- Topic: midterm
- Replies: 16
- Views: 530
Re: midterm
From my experience in 14A, Dr. Lavelle typically releases the scores about one week after the exam. However, we all took it on the same day this quarter so it may be a little different.
- Sat Jan 23, 2021 11:21 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Calculator for exams
- Replies: 28
- Views: 822
Re: Calculator for exams
I've been using the TI-84 Plus CE claculator and it's been okay to use so far. I honestly think any calculator along those lines should work.
- Sat Jan 23, 2021 11:18 pm
- Forum: General Science Questions
- Topic: Chem Jokes
- Replies: 28
- Views: 1536
Re: Chem Jokes
I would add the go-to classic chemistry joke in here, but all the good ones Argon.
- Sat Jan 23, 2021 11:17 pm
- Forum: Phase Changes & Related Calculations
- Topic: Bond Enthalpies
- Replies: 4
- Views: 91
Re: Bond Enthalpies
The most accurate method for bond enthalpies is probably Hess's Method and using the summation equation of the standard enthalpies of formation.
- Sat Jan 23, 2021 11:14 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Acids and Bases
- Replies: 8
- Views: 338
Re: Acids and Bases
Acids and bases act in a certain strict way. It's just a matter of how you look at them. Whether it's through receiving a proton of donating an electron, it is essentially one and the same.
- Sat Jan 23, 2021 11:12 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Sapling vs. Textbook Problems
- Replies: 8
- Views: 396
Re: Sapling vs. Textbook Problems
While I think that sapling is also a great learning method, the tests lay more along the lines of the textbook problems based on my experience last quarter.
- Sun Jan 17, 2021 2:53 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: q vs k
- Replies: 62
- Views: 2368
Re: q vs k
When Q = K, the reaction is at equilibrium. K will only change with a temperature change, but Q will change depending on factors such as changes in concentration and pressure.
- Sun Jan 17, 2021 2:49 pm
- Forum: Student Social/Study Group
- Topic: Motivation
- Replies: 39
- Views: 1729
Re: Motivation
Keeping a planner and reminding myself that I do not always need to be doing something for school helped me become more motivated and use the time that I do dedicate towards school be more efficient.
- Sun Jan 17, 2021 2:46 pm
- Forum: Ideal Gases
- Topic: Does temperature matter?
- Replies: 19
- Views: 534
Re: Does temperature matter?
Temperature matters as it plays a key role in the ideal gas equation, PV=nRT.
- Sun Jan 17, 2021 2:44 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Kc and Kp
- Replies: 11
- Views: 414
Re: Kc and Kp
You can manipulate the ideal gas equation to convert the equation into terms of either molarity or concentration. It just depends which one you use.
- Sun Jan 17, 2021 2:42 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Heating an Exothermic Reaction
- Replies: 7
- Views: 353
Re: Heating an Exothermic Reaction
By adding heat to the products, the reaction shifts towards the left to restore equilibrium.
- Sun Jan 10, 2021 8:22 pm
- Forum: Ideal Gases
- Topic: Kc vs Kp
- Replies: 109
- Views: 4368
Re: Kc vs Kp
Kp should be used when dealing with gases. Hope this helps!
- Sun Jan 10, 2021 8:21 pm
- Forum: Student Social/Study Group
- Topic: Group Me
- Replies: 6
- Views: 303
Re: Group Me
Hi Lucy! This is the link for the class GroupMe. https://groupme.com/join_group/62288203/dSSkobMS
- Sun Jan 10, 2021 8:20 pm
- Forum: Ideal Gases
- Topic: Units for Pressure
- Replies: 41
- Views: 2399
Re: Units for Pressure
I believe we will mostly be using atm for the extent of this class.
- Sun Jan 10, 2021 8:18 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: aqueous solutions
- Replies: 9
- Views: 341
Re: aqueous solutions
The aqueous solutions must be included.
- Fri Dec 11, 2020 12:35 pm
- Forum: Amphoteric Compounds
- Topic: Sapling Week 10 HW Question 2
- Replies: 8
- Views: 631
Re: Sapling Week 10 HW Question 2
An amphoteric substance has the liberty to either gain a proton or lose a proton. Usually, compounds with multiple Hydrogens can act as amphoteric substances.
- Fri Dec 11, 2020 12:32 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Why does nickel have an expanded octet?
- Replies: 3
- Views: 274
Re: Why does nickel have an expanded octet?
Since Nickel is in the d-orbital, it is able to access its expanded octet!
- Fri Dec 11, 2020 12:31 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2985835
Re: Post All Chemistry Jokes Here
I would post all my good chemistry jokes but all of them Argon.
- Fri Dec 11, 2020 12:30 pm
- Forum: Amphoteric Compounds
- Topic: Amphoteric
- Replies: 8
- Views: 534
Re: Amphoteric
I'm pretty sure this isn't going to be on the final but it exhibits either acid characteristics or base characteristics depending on what it is being added to.
- Fri Dec 11, 2020 12:28 pm
- Forum: Properties of Electrons
- Topic: How can an electron be excited?
- Replies: 7
- Views: 405
Re: How can an electron be excited?
As long as the energy from the photon is greater than the energy of the work function, electrons will eject using kinetic energy. These electrons move to higher energy states, gaining energy which makes them excited.
- Sun Dec 06, 2020 1:20 pm
- Forum: Naming
- Topic: Sapling Week 9 #5
- Replies: 3
- Views: 197
Re: Sapling Week 9 #5
I think we are expected to know them. I would just memorize them just to be safe. Knowing them can never hurt anyway.
- Sun Dec 06, 2020 1:19 pm
- Forum: Student Social/Study Group
- Topic: Tips for Staying Focused
- Replies: 64
- Views: 3570
Re: Tips for Staying Focused
To be most efficient in my studying, I usually put on some music (not super intense) and let it play while I study. Sometimes an hour of studying will go by and I won't even notice. Also, I'd recommend to not study on your bed.
- Sun Dec 06, 2020 1:17 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Flashcards
- Replies: 8
- Views: 264
Re: Flashcards
To be honest, I think it just depends on what kind of a learner you are. For me personally, doing applicational problems with the content I'm trying to memorize helps things stick more but if flash cards have worked for you in the past, then that's a really good way to memorize.
- Sat Nov 28, 2020 2:00 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Class Grading Scale
- Replies: 7
- Views: 370
Re: Class Grading Scale
I have this question too. Does anyone know how the class has been curved in previous years.
- Sat Nov 28, 2020 1:59 pm
- Forum: Administrative Questions and Class Announcements
- Topic: fall 2020 final
- Replies: 17
- Views: 798
Re: fall 2020 final
The final is held on the weekend. It isn't during class time or discussion section.
- Sat Nov 28, 2020 1:59 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Sapling Wk8 Q. 18, Determining Molecular Shape
- Replies: 10
- Views: 457
Re: Sapling Wk8 Q. 18, Determining Molecular Shape
Yes, molecules are read from left to right.
- Sat Nov 28, 2020 1:58 pm
- Forum: Administrative Questions and Class Announcements
- Topic: 14B
- Replies: 11
- Views: 675
Re: 14B
We will have tests during class time for Chem 14B so I don't recommend scheduling another class at the same time.
- Sat Nov 28, 2020 1:56 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Polar vs. nonpolar bonds/molecules
- Replies: 8
- Views: 431
Re: Polar vs. nonpolar bonds/molecules
Drawing the molecule out really helps visualize if it's nonpolar or polar. Since the arrows both point outward from the Carbon to the Oxygens, the dipole moments cancel out and therefore the molecule in nonpolar.
- Sat Nov 28, 2020 1:54 pm
- Forum: Hybridization
- Topic: Sapling #12
- Replies: 29
- Views: 1003
Re: Sapling #12
The hybridization is the electron density around the atom. Double and triple bonds also just count as a single region of electron density.
- Sat Nov 28, 2020 1:53 pm
- Forum: Student Social/Study Group
- Topic: Exercising Our Minds and Bodies
- Replies: 120
- Views: 15166
Re: Exercising Our Minds and Bodies
I try to run for a little everyday but sometimes it's just hard to find motivation. It definitely helps me mentally to exercise though.
- Sat Nov 28, 2020 1:51 pm
- Forum: Student Social/Study Group
- Topic: Midterm Exam Questions
- Replies: 16
- Views: 700
Re: Midterm Exam Questions
Just to be safe, I wouldn't speak upon it on here but you can go over them with your TA!
- Sat Nov 28, 2020 1:50 pm
- Forum: Lewis Structures
- Topic: lewis structure resonance
- Replies: 5
- Views: 310
Re: lewis structure resonance
They aren't incorrect; however better formal charges are always preferred and more ideal.
- Sat Nov 28, 2020 1:48 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Double/Triple Bonds and Polarity
- Replies: 8
- Views: 358
Re: Double/Triple Bonds and Polarity
The molecule is an overall nonpolar molecule since the dipoles do cancel our regardless of bond length.
- Sat Nov 28, 2020 1:46 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Final
- Replies: 15
- Views: 547
Re: Final
I would think that we are going to use respondus and while the final won't be in our discussion sections, we're probably still going to be monitored somehow.
- Sat Nov 28, 2020 1:45 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Polarity and Shape
- Replies: 13
- Views: 620
Re: Polarity and Shape
You can draw out the molecule and if it has dipoles that do not cancel, it is polar. You can also have a nonpolar molecule with polar bonds.
- Sun Nov 15, 2020 9:39 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Missed chem community posts
- Replies: 12
- Views: 568
Re: Missed chem community posts
I had this exact same question. I tried emailing my TA about it a few times but I didn't hear back so thank you so much for clarifying. It was stressing me out.
- Sun Nov 15, 2020 9:38 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Oxidation Sapling 9
- Replies: 6
- Views: 394
Re: Oxidation Sapling 9
Since there are 4 Oxygens, each with a charge of -2, the total charge from Oxygens is -8. Since the overall charge on ClO4- is -1. The charge on Cl must be +7, and that is the oxidation number on Cl.
- Sun Nov 15, 2020 9:35 pm
- Forum: General Science Questions
- Topic: Midterm 2
- Replies: 12
- Views: 723
Re: Midterm 2
I believe it will contain material from the last 8 points on Outline 2 and all of Outline 3.
- Sun Nov 15, 2020 9:33 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: Sapling # 20
- Replies: 6
- Views: 651
Re: Sapling # 20
All molecules and compounds see London Dispersion forces. Dipole-dipole forces are shown as CH3CHO is a polar compound. Therefore, the differences in electronegativity lead to an unequal sharing of electrons and the presence of dipole - dipole forces.
- Sun Nov 15, 2020 9:29 pm
- Forum: Electronegativity
- Topic: Electronegativity
- Replies: 9
- Views: 417
Re: Electronegativity
Electronegativity decreases down a group as more shells get added. The addition of these valence shells results in the electrons being further away from the nucleus and therefore they see a smaller attraction to it.
- Sun Nov 15, 2020 9:19 pm
- Forum: Ionic & Covalent Bonds
- Topic: midterm 2: knowing compounds
- Replies: 14
- Views: 535
Re: midterm 2: knowing compounds
I think they will be provided. I don't think we are expected to know compounds that extensively right now.
- Sun Nov 15, 2020 9:18 pm
- Forum: Ionic & Covalent Bonds
- Topic: Sapling week 5 & 6 #16
- Replies: 7
- Views: 225
Re: Sapling week 5 & 6 #16
The Hydrogen must be able to create a strong dipole moment to bond to an electronegative element therefore bonding to another electronegative element will allow for the electrons to be shared unequally and allow for Hydrogen bonding to occur.
- Sun Nov 15, 2020 9:15 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Oxidation numbers
- Replies: 3
- Views: 99
Re: Oxidation numbers
I don't think we need to know them in a lot of depth. However, there was a sapling problem on it so I would recommend reviewing how to do them but I don't think we will need to know how to do them extensively.
- Sun Nov 15, 2020 9:14 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: S and P electrons
- Replies: 14
- Views: 1387
Re: S and P electrons
Because the p-orbitals are further away from the nucleus, it takes more energy to keep the electron while the s-orbitals are closer to the nucleus and see a stronger attraction to it therefore less energy is needed.
- Sun Nov 15, 2020 9:13 pm
- Forum: Lewis Structures
- Topic: Expanded Octets
- Replies: 7
- Views: 335
Re: Expanded Octets
Atoms in n=3 or higher have d-orbitals in valence shells that can accommodate additional e-s. For example, phosphorus can accommodate 10 e-s using 1 d-orbital.
- Sun Nov 15, 2020 9:10 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: Van der Waals vs London Dispersion
- Replies: 10
- Views: 596
Re: Van der Waals vs London Dispersion
London dispersion is just another name for Van Der Waals. They are interchangeable. I don't think their distinction is important to know for the upcoming midterm.
- Sun Nov 15, 2020 9:09 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Sapling #20
- Replies: 12
- Views: 616
Re: Sapling #20
The hydrogen must be bonded to an electronegative atom so it can create a dipole moment strong enough to create a Hydrogen bond. Electronegative elements that can Hydrogen bond include F, O, and N.
- Sun Nov 15, 2020 9:06 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Sapling #9 week 5/6
- Replies: 13
- Views: 664
Re: Sapling #9 week 5/6
The formal charge that is closest to zero is most stable therefore the structure with low formal charges closest to zero are preferred.
- Sun Nov 15, 2020 9:05 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Sapling W6 #9
- Replies: 2
- Views: 83
Re: Sapling W6 #9
The overall charge is -1. Since there are 4 Oxygens, each with a charge of -2. The charge on Cl must be +7 since (oxidation number on Cl) + (-2)4 = -1.
- Sun Nov 15, 2020 5:26 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Sapling week 5 & 6 #5
- Replies: 20
- Views: 719
Re: Sapling week 5 & 6 #5
The formal charge on Carbon should be -2. Since Crabon has 4 valence electrons, 2 pairs of shared electrons, and 2 lone pairs of electrons. 4-(2+4) = -2. Hope this helps!
- Sun Nov 15, 2020 5:24 pm
- Forum: Dipole Moments
- Topic: Sapling #19
- Replies: 12
- Views: 533
Re: Sapling #19
It should say SO2 instead. Dr. Lavelle addressed this issue.
- Sun Nov 15, 2020 5:21 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Drawing the lone pairs on the central atom
- Replies: 5
- Views: 279
Re: Drawing the lone pairs on the central atom
The presence of the lone pairs most definitely contributes to the shape of the molecule but I believe we aren't getting into bond angles and shapes for the purposes of Midterm 2. I believe we are after though!
- Sun Nov 15, 2020 5:18 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Which has more ionic character?
- Replies: 11
- Views: 1749
Re: Which has more ionic character?
As ionic radius increases, the electrons show less attraction for the nucleus and thus the atom is more readily polarizable leading to a decrease in ionic character.
- Sun Nov 15, 2020 5:16 pm
- Forum: General Science Questions
- Topic: Midterm #2
- Replies: 11
- Views: 512
Re: Midterm #2
I believe everything from where we ended off for on outline 2 up to Wednesday's lecture will be included on the midterm.
- Sun Nov 15, 2020 5:15 pm
- Forum: Resonance Structures
- Topic: bond length
- Replies: 37
- Views: 1425
Re: bond length
We don't need to know how to calculate them but we do need to know which bond lengths are stronger and shorter compared to which bond lengths are longer and weaker.
- Sun Nov 15, 2020 5:13 pm
- Forum: Lewis Structures
- Topic: Central Atom
- Replies: 20
- Views: 620
Re: Central Atom
The least electronegative atom goes in the center so for example Carbon would go in the center instead of Oxygen.
- Sun Nov 15, 2020 5:12 pm
- Forum: Properties of Light
- Topic: Videos
- Replies: 12
- Views: 592
Re: Videos
The Organic Chemistry Tutor is really good! I would also recommend taking the module assessments and watching Professor Lavelle's modules on topics you need clarification on.