Search found 99 matches
- Fri Mar 12, 2021 8:02 am
- Forum: Student Social/Study Group
- Topic: It is possible to study for the final in one day?
- Replies: 44
- Views: 4661
Re: It is possible to study for the final in one day?
It's been said that people learn things faster under pressure! Don't give up! :D
- Fri Mar 12, 2021 8:01 am
- Forum: Student Social/Study Group
- Topic: Chemistry Community Posts
- Replies: 12
- Views: 745
Re: Chemistry Community Posts
Just count them! :)
- Fri Mar 12, 2021 8:00 am
- Forum: Student Social/Study Group
- Topic: Planning on dorming in the Fall?
- Replies: 61
- Views: 4200
Re: Planning on dorming in the Fall?
I am deciding between renting an apartment or living in the dorm
- Fri Mar 12, 2021 7:58 am
- Forum: Student Social/Study Group
- Topic: What do you miss / What are you looking forward to?
- Replies: 92
- Views: 13086
Re: What do you miss / What are you looking forward to?
I am looking forward to make more friends at UCLA and hanging around in LA!
- Fri Mar 12, 2021 7:57 am
- Forum: Student Social/Study Group
- Topic: Balance / Self Care Tips
- Replies: 62
- Views: 4020
Re: Balance / Self Care Tips
Exercise your body and mind. ---Professor Lavelle
- Fri Mar 12, 2021 7:56 am
- Forum: Student Social/Study Group
- Topic: How are y'all doing?
- Replies: 46
- Views: 3013
Re: How are y'all doing?
I am very stressed and burnt out now, but I still take more courses next quarter to challenge myself :(
- Fri Mar 12, 2021 7:54 am
- Forum: Student Social/Study Group
- Topic: Note Taking
- Replies: 145
- Views: 19448
Re: Note Taking
I use handwriting to help myself remember and understand things.
- Fri Mar 12, 2021 7:49 am
- Forum: Student Social/Study Group
- Topic: Review Videos
- Replies: 17
- Views: 1081
Re: Review Videos
So many people are advocating for Organic Tutor! I am gonna have a try.
- Fri Mar 12, 2021 7:48 am
- Forum: Student Social/Study Group
- Topic: Exam Review
- Replies: 10
- Views: 636
Re: Exam Review
Email your TA! I agree with that.
- Fri Mar 12, 2021 7:47 am
- Forum: Student Social/Study Group
- Topic: Chemistry Community Posts
- Replies: 16
- Views: 1013
Re: Chemistry Community Posts
I think 50 points is not divided weekly, as long as you make enough posts before the closure of chemistry community.
- Fri Mar 12, 2021 7:45 am
- Forum: Student Social/Study Group
- Topic: Low Grades & Graduate School
- Replies: 22
- Views: 1988
Re: Low Grades & Graduate School
I am worried about my grades too this quarter. You are not the only one!
- Fri Mar 12, 2021 7:44 am
- Forum: Student Social/Study Group
- Topic: Low Grades & Graduate School
- Replies: 22
- Views: 1988
Re: Low Grades & Graduate School
If you pass the class, you won't be able to retake it, but honestly I wouldn't sweat it too much. Your GPA is definitely important, but it doesn't define you obviously. I would say it's more important that if you do choose to continue on the series, you do your best to do better in 14C and CL. If y...
- Fri Mar 12, 2021 7:43 am
- Forum: Student Social/Study Group
- Topic: Clubs/Organizations
- Replies: 9
- Views: 769
Re: Clubs/Organizations
Only one, CSPF.
- Fri Mar 12, 2021 7:42 am
- Forum: Student Social/Study Group
- Topic: How do you deal with burnout?
- Replies: 144
- Views: 21012
Re: How do you deal with burnout?
Have a lot of sleep!
- Sun Mar 07, 2021 7:32 am
- Forum: Student Social/Study Group
- Topic: Playlist
- Replies: 86
- Views: 9035
Re: Playlist
Beethoven sonata "Tempest"
- Sun Mar 07, 2021 7:31 am
- Forum: Student Social/Study Group
- Topic: Book Recommendations
- Replies: 135
- Views: 19520
Re: Book Recommendations
The Story of a Stone, or Dream of the Red Chamber
- Sun Mar 07, 2021 7:28 am
- Forum: Student Social/Study Group
- Topic: Fave movie/show
- Replies: 67
- Views: 5725
Re: Fave movie/show
Game of Thrones definitely
- Sun Mar 07, 2021 7:28 am
- Forum: Student Social/Study Group
- Topic: Fave food
- Replies: 266
- Views: 48241
Re: Fave food
spaghtti
- Sun Mar 07, 2021 7:27 am
- Forum: Student Social/Study Group
- Topic: Fave food
- Replies: 266
- Views: 48241
Re: Fave food
Strawberry mango smoothie
- Sun Mar 07, 2021 7:26 am
- Forum: Student Social/Study Group
- Topic: Fave food
- Replies: 266
- Views: 48241
Re: Fave food
Sushi!
- Sun Mar 07, 2021 7:26 am
- Forum: Student Social/Study Group
- Topic: Fave food
- Replies: 266
- Views: 48241
Re: Fave food
Matcha ice cream!
- Sun Mar 07, 2021 7:23 am
- Forum: Student Social/Study Group
- Topic: We made it through Midterm 2!
- Replies: 71
- Views: 4946
Re: We made it through Midterm 2!
I am already exhausted after midterm 2
- Sun Mar 07, 2021 7:22 am
- Forum: Student Social/Study Group
- Topic: We made it through Midterm 2!
- Replies: 71
- Views: 4946
Re: We made it through Midterm 2!
My grades on midterm 2 looks so bad
- Sun Mar 07, 2021 7:21 am
- Forum: Student Social/Study Group
- Topic: Final
- Replies: 63
- Views: 4250
Re: Final
Do some past paper
- Sun Mar 07, 2021 7:21 am
- Forum: Student Social/Study Group
- Topic: Final
- Replies: 63
- Views: 4250
Re: Final
Attend the workshop sessions
- Sun Mar 07, 2021 7:20 am
- Forum: Student Social/Study Group
- Topic: Final
- Replies: 63
- Views: 4250
Re: Final
Also do the textbook problems
- Sun Mar 07, 2021 7:19 am
- Forum: Student Social/Study Group
- Topic: Final
- Replies: 63
- Views: 4250
Re: Final
Doing some workshop problems will help
- Sun Mar 07, 2021 7:19 am
- Forum: Student Social/Study Group
- Topic: Final
- Replies: 63
- Views: 4250
Re: Final
Gosh I am so stressed about this.
- Sun Mar 07, 2021 7:18 am
- Forum: Student Social/Study Group
- Topic: Final
- Replies: 63
- Views: 4250
Re: Final
Gosh I am so stressed about this.
- Sun Mar 07, 2021 7:18 am
- Forum: Student Social/Study Group
- Topic: Final
- Replies: 63
- Views: 4250
Re: Final
Gosh I am so stressed about this.
- Sun Mar 07, 2021 7:17 am
- Forum: Student Social/Study Group
- Topic: Final
- Replies: 63
- Views: 4250
Re: Final
Gosh I am so stressed about this.
- Sun Mar 07, 2021 7:16 am
- Forum: Student Social/Study Group
- Topic: Chem Community Points
- Replies: 35
- Views: 1861
Re: Chem Community Points
I am so stressed about this
- Sun Mar 07, 2021 7:15 am
- Forum: Student Social/Study Group
- Topic: Chem Community Points
- Replies: 35
- Views: 1861
Re: Chem Community Points
I am so stressed about this
- Sun Mar 07, 2021 7:15 am
- Forum: Student Social/Study Group
- Topic: Chem Community Points
- Replies: 35
- Views: 1861
Re: Chem Community Points
I am so stressed about this
- Sun Mar 07, 2021 7:15 am
- Forum: Student Social/Study Group
- Topic: Chem Community Points
- Replies: 35
- Views: 1861
Re: Chem Community Points
I am so stressed about this
- Sun Mar 07, 2021 7:14 am
- Forum: Student Social/Study Group
- Topic: Chem Community Points
- Replies: 35
- Views: 1861
Re: Chem Community Points
I am so stressed about this
- Sun Mar 07, 2021 7:13 am
- Forum: Student Social/Study Group
- Topic: Chem Community Points
- Replies: 35
- Views: 1861
Re: Chem Community Points
50 points are enough.
- Wed Feb 03, 2021 9:18 pm
- Forum: General Science Questions
- Topic: midterm 1
- Replies: 11
- Views: 1247
Re: midterm 1
Ah that's so true. The midterm problems are so tricky.
- Fri Jan 29, 2021 3:03 am
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Determining relative strength of acids and bases
- Replies: 4
- Views: 10300
Re: Determining relative strength of acids and bases
CH3NH3Cl is an ionic compound, consisting of CH3NH3+ and Cl- ions. The overall salt does not donate protons, the CH3NH3+ ion does (to form H3O+) when the salt is dissociated in water. Cl- is a very weak conjugate base so its basicity is negligible. Therefore the salt is acidic because of CH3NH3+, a...
- Thu Jan 28, 2021 10:18 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Matthew's Workshop - Week 1
- Replies: 7
- Views: 656
Re: Matthew's Workshop - Week 1
Does anyone know how to solve 2.c of Matthew's week 1 worksheet? I tried many times but still get 337.7, while the answer is 6.96M.
- Thu Jan 28, 2021 8:58 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Brooke's Week 4 Workshop
- Replies: 2
- Views: 360
Re: Brooke's Week 4 Workshop
Also, could you post the week 4 practice sheet to the folder? I cannot find it. Thanks!
- Thu Jan 28, 2021 8:49 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Brooke's Week 4 Workshop
- Replies: 2
- Views: 360
Re: Brooke's Week 4 Workshop
Hi, could you post the answer sheets to your previous workshops? Thanks!
- Tue Jan 26, 2021 10:17 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Matthew week 2 WS #6
- Replies: 4
- Views: 354
Re: Matthew week 2 WS #6
They both will lead to the same outcome of the species being protonated. I would try not to confuse yourself with the changing pKa or pKb. If it said that the salt reacted with water then you have to change it to account for hydrolysis but in this case you will still get that the protonated species...
- Sun Jan 24, 2021 4:03 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Matthew week 2 WS #6
- Replies: 4
- Views: 354
Re: Matthew week 2 WS #6
First we shall determine what state the chemical will be in, protonated or neutral. For this we have to look at the pKb and pH. If the pH < pKb, then the protonated species will be more prominent. The chemical is in a more acidic environment which means that there is a higher [H+] present. Rather t...
- Sun Jan 24, 2021 3:01 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K or Kc?
- Replies: 5
- Views: 372
Re: K or Kc?
K is a more general term while Kc refers to the concentration of reactants and products
- Sun Jan 24, 2021 2:59 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Matthew week 2 WS #6
- Replies: 4
- Views: 354
Matthew week 2 WS #6
Does anyone know how to solve this question?
- Sun Jan 24, 2021 2:22 am
- Forum: General Science Questions
- Topic: Matthew UA WS 2 #5
- Replies: 2
- Views: 302
Re: Matthew UA WS 2 #5
First, watch this video: [youtube]https://www.youtube.com/watch?v=50tT_jdkINw[/youtube] It helps a lot. But I'll still explain. First calculate the volume(mL) of NaOH needed, which is 50.51082959mols from this: 7.416\cdot10^{-3}\cdot\frac{100}{1.4682\cdot10^{-2}} . So you now have the mols of NaOH ...
- Sat Jan 16, 2021 5:55 am
- Forum: Ideal Gases
- Topic: n/V = concentration
- Replies: 19
- Views: 2553
Re: n/V = concentration
That part of the lecture was talking about how you can convert between partial pressures and concentrations for gases. PV=nRT is the ideal gas law. If we rearrange it to P=\frac{nRT}{V} , we notice that n/V is just concentration ( M=\frac{mol}{L} ). Therefore, if we ever need to convert partial pre...
- Sat Jan 16, 2021 5:53 am
- Forum: Ideal Gases
- Topic: Ice method
- Replies: 14
- Views: 846
Re: Ice method
Ivy Tan 1E wrote:305405193 wrote:Do any of you have any recommendations on a good YouTube video for explaining Ice tables?
Hi!
https://youtu.be/aJ0KNQ5-KaI here's a short video describing how to use ICE tables using an example. Hope this helps you!!
It helps so much! Thanks!
- Sat Jan 16, 2021 5:51 am
- Forum: Ideal Gases
- Topic: Non-Ideal gases?
- Replies: 26
- Views: 1106
Re: Non-Ideal gases?
This topic sounds to be very hard
- Sat Jan 16, 2021 5:49 am
- Forum: Ideal Gases
- Topic: Kc vs Kp
- Replies: 109
- Views: 5554
Re: Kc vs Kp
Rachel Kho Disc 2G wrote:Also will we need to have the formula that converts Kc to Kp memorized? Or will that be given to us on an equations sheet?
Isn't that equation is PV=nRT?
- Sat Jan 16, 2021 5:41 am
- Forum: Administrative Questions and Class Announcements
- Topic: Sapling Assistance
- Replies: 1
- Views: 507
Re: Sapling Assistance
Thanks! This helps so much.
- Sat Jan 16, 2021 5:39 am
- Forum: Administrative Questions and Class Announcements
- Topic: Matthew's Workshop - Week 1
- Replies: 7
- Views: 656
Re: Matthew's Workshop - Week 1
Thanks for your post!
- Sat Jan 16, 2021 5:38 am
- Forum: Administrative Questions and Class Announcements
- Topic: sapling for chem 14b
- Replies: 3
- Views: 142
Re: sapling for chem 14b
Annika Tamaki 1E wrote:You have to click the use credit option. It didn't work for me yesterday, but I tried it again today and it went through. So if it doesn't work for you, I'd say wait a day :) hope this helps!
It helps so much! Thanks!
- Wed Dec 16, 2020 6:52 am
- Forum: Student Social/Study Group
- Topic: How to study for class
- Replies: 30
- Views: 1559
Re: How to study for class
I also have similar problems. My problem is that the lectures sometimes takes a long time to load and it often stops for loading. I am really grateful to see so many recommendations on learning resources.
- Wed Dec 16, 2020 6:35 am
- Forum: Student Social/Study Group
- Topic: Final Exam
- Replies: 49
- Views: 3051
Re: Final Exam
I barely finished the exam. I rushed on several questions and I am pretty sure they are wrong. Also, I did wrong on questions that I spent a lot of time on, which is quite disappointing.
- Wed Dec 16, 2020 6:30 am
- Forum: Student Social/Study Group
- Topic: Plans for Relaxing After Finals
- Replies: 98
- Views: 21256
Re: Plans for Relaxing After Finals
I am going to travel around.
- Wed Dec 16, 2020 6:30 am
- Forum: Student Social/Study Group
- Topic: Plans for Relaxing After Finals
- Replies: 98
- Views: 21256
Re: Plans for Relaxing After Finals
Joyce Pang 2k wrote:Hibernation.
Haha
- Wed Dec 16, 2020 6:27 am
- Forum: Student Social/Study Group
- Topic: Winter Break
- Replies: 44
- Views: 2811
Re: Winter Break
Just do more practices.
- Wed Dec 16, 2020 6:26 am
- Forum: Hybridization
- Topic: 2F. 15 What does it mean for S-character to increase?
- Replies: 5
- Views: 566
Re: 2F. 15 What does it mean for S-character to increase?
Yes, the s-character is quantified just as you explained it. In terms of question 2F.15, it means that bond angle will increase as s-character increases, as an sp2 orbital has 33% s-character, while an sp3 orbital has 25% s-character. Thank you for your help! I don't remember learning about this in...
- Wed Dec 16, 2020 6:23 am
- Forum: Hybridization
- Topic: Hybridization of CO2
- Replies: 5
- Views: 445
Re: Hybridization of CO2
I think it is correct.
- Wed Dec 16, 2020 6:21 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: A question from the final
- Replies: 5
- Views: 484
A question from the final
Why is the shape of S_{2}O_{3}^{2-} tetrahedral? I drew a trigonal pyramidal shape and find that also works, which has a S-S bond in the center, and 2 oxygen bind to one S and 1 oxygen binds to the other S, but I googled after the exam and found that the shape is tetrahedral.
- Wed Dec 16, 2020 6:14 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: What are the bond angles for T shaped?
- Replies: 21
- Views: 8837
Re: What are the bond angles for T shaped?
Michelle Magana 2B wrote:T shape molecular geometry has <90 degree bond angles. I also attached a chart which you can refer to.
This chart helps so much!
- Wed Dec 16, 2020 6:13 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: textbook problem 2E 25
- Replies: 2
- Views: 273
Re: textbook problem 2E 25
In VSEPR theory, the lone pair forces the molecular geometry of SF4 into a see-saw shape. Two of the S-F bonds are pointing away from each other, and their bond dipoles cancel. But the other two S-F dipoles are pointing "down". Their bond dipoles do not cancel, so the molecule is polar.
- Wed Dec 16, 2020 6:09 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Recognizing ligand binding sites
- Replies: 5
- Views: 522
Re: Recognizing ligand binding sites
1 lone pair to form 1 bond: monodentate
2 lone pairs to form 2 bonds: bidentate ligand
3 lone pairs to form 3 bonds: tridentate ligand
6 lone pairs to form 6 bonds: hexadentate ligand
2 lone pairs to form 2 bonds: bidentate ligand
3 lone pairs to form 3 bonds: tridentate ligand
6 lone pairs to form 6 bonds: hexadentate ligand
- Wed Dec 16, 2020 6:08 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Ligands
- Replies: 8
- Views: 473
Re: Ligands
It can have multiple ligands.
- Wed Dec 16, 2020 6:07 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Polydentate Ligands
- Replies: 5
- Views: 400
Re: Polydentate Ligands
For those textbook problems, I drew out the Lewis structures and looked for atoms that had lone pairs. For example, for water, the oxygen has lone pairs, so it can be a monodentate ligand (it's not a bidentate ligand because the two lone pairs are on the same bonding site). At the UA session earlie...
- Wed Dec 16, 2020 6:03 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Square planar complex vs tetrahedral complex
- Replies: 6
- Views: 3487
Re: Square planar complex vs tetrahedral complex
Tetrahedral is represented as AX4, while square planar is AX4E2, as square planar has two more electron domains. Prof Lavelle said this shape is not common at all, like XeF4, but in Sapling it says square planar is a common shape. This is why I am confused.
- Wed Dec 16, 2020 5:58 am
- Forum: Industrial Examples
- Topic: Chemotherapy
- Replies: 22
- Views: 1770
Re: Chemotherapy
I only remember Dr. Lavelle going over Cisplatin-- do we have to know others? I'm pretty sure the only one we'd have to know is cisplatin, and possibly why transplatin is its ineffective counterpart. I know for transplatin it is ineffective because of the geometry (correct me if I am wrong). Cispla...
- Wed Dec 16, 2020 5:57 am
- Forum: Naming
- Topic: Textbook Question 9C.1
- Replies: 5
- Views: 520
Re: Textbook Question 9C.1
I'm assuming you meant [Co(CN)5(OH2)]2-. For that, the name would be Aquapentacyanocobaltate (III) Aqua comes first alphabetically. Then cyano and we have to add penta- because there are 5. After that, we add the transition metal name and add -ate because the complex is negative. Add the charge of ...
- Wed Dec 16, 2020 5:55 am
- Forum: Naming
- Topic: K[Cu(en)2 (CN)2 ]
- Replies: 7
- Views: 628
Re: K[Cu(en)2 (CN)2 ]
K has a positive charge of 1 and en is neutral, CN has a negative charge of 1 and there are two of them, so Cu has to be +1
- Wed Dec 16, 2020 5:51 am
- Forum: Naming
- Topic: How to determine the charge of ligands?
- Replies: 4
- Views: 445
How to determine the charge of ligands?
I am confused how to determine the charge of each specific ligand, like Cl, NH3, H2O, NH2, etc.
- Wed Dec 16, 2020 5:46 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Why is CO (carbon monoxide) monodentate?
- Replies: 6
- Views: 1683
Re: Why is CO (carbon monoxide) monodentate?
H2O also has two lone pairs but it is a monodentate as well. I read some explanations online and they say that it is because water only has one donor atom and in polydentates there are more than one donor atoms. The other lone pair on the same atom cannot bond to the metal due to geometrical reasons.
- Wed Dec 16, 2020 5:40 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Heme Complex Coordination Compound
- Replies: 3
- Views: 675
Re: Heme Complex Coordination Compound
Heme complex is formed when a Fe is bound to a porphyrin ligand, and the porphyrin ligand is a cake-like molecule, a tetra dentate in the shape of square planar with 4 nitrogens.
- Wed Dec 16, 2020 5:36 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Chelating ligands
- Replies: 4
- Views: 345
Re: Chelating ligands
I completely ignored this part in the lecture, thank you for posting this!
- Wed Dec 16, 2020 5:33 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Cis Trans Isomers
- Replies: 7
- Views: 505
Re: Cis Trans Isomers
It did appear in the exam and I did it wrong highly possibly.
- Wed Dec 16, 2020 5:30 am
- Forum: Polyprotic Acids & Bases
- Topic: Textbook 6C.19
- Replies: 7
- Views: 532
Re: Textbook 6C.19
H-Cl bond is longer than H-F bond because Cl has larger atomic radius than F, so it is easier to break. Strong acid loses H+ more easily, and also the resulting anion is stabler. For HClO, the Cl in the Cl-O anion delocalize electron to a larger degree than Br in Br-O, and therefore HClO has greater...
- Wed Dec 16, 2020 5:23 am
- Forum: Amphoteric Compounds
- Topic: Amphoteric Compounds trend
- Replies: 2
- Views: 312
Re: Amphoteric Compounds trend
Prof. Lavelle posted picture of the diagonal band of metal oxides in the periodic table.
And besides these metal oxides, I only know there is H_{2}PO_{4}^{2-}
And besides these metal oxides, I only know there is H_{2}PO_{4}^{2-}
- Wed Dec 16, 2020 5:15 am
- Forum: Administrative Questions and Class Announcements
- Topic: Saying Thank You to Dr. Lavelle
- Replies: 490
- Views: 633274
Re: Saying Thank You to Dr. Lavelle
Dear Prof. Lavelle,
Thank you for explaining the concepts so well. You did a great job talking about the links to further knowledge in physiology, pharmacology, medicine, etc. Also, thank you for your support during this time of difficulties.
Nancy
Thank you for explaining the concepts so well. You did a great job talking about the links to further knowledge in physiology, pharmacology, medicine, etc. Also, thank you for your support during this time of difficulties.
Nancy
- Wed Dec 16, 2020 5:06 am
- Forum: Student Social/Study Group
- Topic: Final Jitters
- Replies: 457
- Views: 427028
Re: Final Jitters
Do some massage :)
- Sat Dec 12, 2020 11:28 pm
- Forum: Identifying Acidic & Basic Salts
- Topic: rules for determining
- Replies: 7
- Views: 597
Re: rules for determining
Strong Acid + Strong Base -> neutral salt
Strong Acid + Weak Base -> acidic salt
Strong Base + Weak Acid -> basic salt
Strong Acid + Weak Base -> acidic salt
Strong Base + Weak Acid -> basic salt
- Sat Dec 12, 2020 11:27 pm
- Forum: Identifying Acidic & Basic Salts
- Topic: Helpful Video (Acidic & Basic Salts)
- Replies: 4
- Views: 514
Re: Helpful Video (Acidic & Basic Salts)
Thanks for the videos!
- Sat Dec 12, 2020 11:26 pm
- Forum: Identifying Acidic & Basic Salts
- Topic: Identifying Salt pH
- Replies: 6
- Views: 541
Re: Identifying Salt pH
I think it is like this too.
- Wed Dec 02, 2020 7:15 am
- Forum: Sigma & Pi Bonds
- Topic: Rotation
- Replies: 16
- Views: 976
Re: Rotation
Write it in a straightforward way:
single bond = sigma-bond
double bond = sigma-bond + pi-bond
triple bond = sigma-bond + 2 pi-bonds
single bond = sigma-bond
double bond = sigma-bond + pi-bond
triple bond = sigma-bond + 2 pi-bonds
- Wed Dec 02, 2020 7:00 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: H20 to H2S
- Replies: 4
- Views: 526
Re: H20 to H2S
Hydrogen bonding can happen only when the hydrogen is in a polar molecule and the other atom in the hydrogen bonding is electronegative (N, F, O).
I think in this case, water would prefer to form hydrogen bond within itself rather than hydrogen bonding with H2S.
I think in this case, water would prefer to form hydrogen bond within itself rather than hydrogen bonding with H2S.
- Wed Dec 02, 2020 6:49 am
- Forum: General Science Questions
- Topic: midterm 2 answers
- Replies: 30
- Views: 2392
Re: midterm 2 answers
Francesca_Borchardt_2L wrote:I know for midterm 1, my TA had us set up appointments to go over the midterm with him. I am assuming the same is going to happen for Midterm 2 too.
Thanks! That helps so much. I also want to go over midterm 2.
- Wed Dec 02, 2020 6:40 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Energy level of orbitals
- Replies: 5
- Views: 429
Re: Energy level of orbitals
Besides the general trend s<p<d<f, electrons enter 4s orbital before 3d because the 4s is initially Lower in energy. From Scandium (Sc) onwards, the 3d orbital becomes Lower than 4s.
We write 3d before 4s in configuration, like K [Ar]4s1, Ca [Ar]4s2 with no 3d orbitals
We write 3d before 4s in configuration, like K [Ar]4s1, Ca [Ar]4s2 with no 3d orbitals
- Wed Dec 02, 2020 6:34 am
- Forum: Administrative Questions and Class Announcements
- Topic: 14B
- Replies: 11
- Views: 809
Re: 14B
chinmayeec 3L wrote:Dr. Lavelle sent an email saying that students must keep scheduled Chem 14B class time open because we will have tests during class time. So yes, you shouldn't overlap it with another lecture.
Hope that helps!
It helps so much! I missed that email.
- Wed Dec 02, 2020 6:01 am
- Forum: Administrative Questions and Class Announcements
- Topic: Finals Week
- Replies: 12
- Views: 791
Re: Finals Week
https://lavelle.chem.ucla.edu/wp-content/supporting-files/Chem14A/Final_Review_Sessions_14A.pdf
Final 11:30am – 1pm, Sunday December 13.
Alternative time for international students, 8pm – 9:30pm, Sunday December 13.
Final 11:30am – 1pm, Sunday December 13.
Alternative time for international students, 8pm – 9:30pm, Sunday December 13.
- Wed Dec 02, 2020 5:51 am
- Forum: Student Social/Study Group
- Topic: How are you?
- Replies: 154
- Views: 17583
Re: How are you?
December is so intense.
- Wed Dec 02, 2020 5:37 am
- Forum: Hybridization
- Topic: when to use hybridization
- Replies: 2
- Views: 218
Re: when to use hybridization
The shortcut I use is that: if an atom forms more than one bond with another atom, then there are e- in unhybridized orbitals. This is because the energy level difference between, for example, 2p and 2sp2 is smaller than the energy of e- repulsion. The unhybridized orbitals (perpendicular to 2sp2 o...
- Wed Dec 02, 2020 5:35 am
- Forum: Hybridization
- Topic: Sigma and Pi bonds
- Replies: 29
- Views: 2903
Re: Sigma and Pi bonds
sigma-bond: 2 orbitals, each with 1 electron, interact end-to-end to form 1 sigma-bond, allow bond atoms to rotate, resulting sigmabond has electron density with cylindrical symmetry around internuclear axis pi-bond: p orbitals overlap side-by-side, do not allow atoms to rotate (rigid), and the elec...
- Wed Dec 02, 2020 5:28 am
- Forum: Student Social/Study Group
- Topic: Final Exam Study Tips
- Replies: 48
- Views: 2792
Re: Final Exam Study Tips
My high school chemistry teacher recommended us to write down everything you know on a blank sheet of paper, and this process will help you recall the knowledge you gained, especially the bulky parts, like the chart of different chemical geometries and their bond angles, or the elements that do not ...
- Wed Dec 02, 2020 5:22 am
- Forum: Ionic & Covalent Bonds
- Topic: Polar and Nonpolar
- Replies: 37
- Views: 2017
Re: Polar and Nonpolar
The dipoles are like vectors and sometimes they cancel out each other.
- Wed Dec 02, 2020 5:14 am
- Forum: Administrative Questions and Class Announcements
- Topic: Textbook Issue
- Replies: 5
- Views: 347
Re: Textbook Issue
The names of the chemicals in problem 2E.4 are (a) SeF6 (b)IF7
- Wed Dec 02, 2020 5:04 am
- Forum: Student Social/Study Group
- Topic: Happy Thanksgiving!
- Replies: 39
- Views: 2318
Re: Happy Thanksgiving!
I slept through Thanksgiving but it is still fun :)
- Wed Dec 02, 2020 5:02 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angles
- Replies: 13
- Views: 1587
Re: Bond Angles
I would say first draw the Lewis structure and determine the number of lone pairs, and then determine its shape. The existence of lone pairs explain the difference between trigonal planar and trigonal pyramid and between tetrahedral and square planar, and both pairs of shapes have the same coordinat...
- Wed Dec 02, 2020 4:57 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordination numbers and shapes
- Replies: 3
- Views: 368
Re: Coordination numbers and shapes
Below are the several shapes we've learned in class: Coordination number 2 (not very common): linear, bent Coordination number 3: trigonal planar, trigonal pyramid Coordination number 4: tetrahedral, square planar Coordination number 5: trigonal bipyramid Coordination number 6: octahedral After iden...
- Wed Dec 02, 2020 4:39 am
- Forum: Student Social/Study Group
- Topic: Big Sad: Midterm 2
- Replies: 86
- Views: 8328
Re: Big Sad: Midterm 2
Here is a person who did not post anything on chemistry community until week 9 and is also worried about passing the course :(