Thank you Dr. Lavelle!!
Your lectures, sapling, the step-up sessions, the workshops, the final review sessions, and especially the music and CHEMISTRY COMMUNITY!! Chem 14A and Chem 14B made me fall in love with chemistry again!!
Search found 106 matches
- Sat Mar 13, 2021 9:00 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Saying Thank You to Dr. Lavelle
- Replies: 490
- Views: 627830
- Sat Mar 13, 2021 8:57 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: What was your favorite chem topic?
- Replies: 137
- Views: 13238
Re: What was your favorite chem topic?
electrochemistry for sure!
- Sat Mar 13, 2021 8:57 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Spring Forward March 14! Make sure to set your clocks!
- Replies: 18
- Views: 1944
Re: Spring Forward March 14! Make sure to set your clocks!
omg thank you so much!!
- Sat Mar 13, 2021 8:56 pm
- Forum: Student Social/Study Group
- Topic: Spring Quarter
- Replies: 60
- Views: 3955
Re: Spring Quarter
I didn't get a seat in chem 14C :(
I guess I won't be taking any chem classes in the spring
I guess I won't be taking any chem classes in the spring
- Sat Mar 13, 2021 8:55 pm
- Forum: Student Social/Study Group
- Topic: Final Jitters
- Replies: 457
- Views: 422823
Re: Final Jitters
just take deep breaths and close your eyes to shut out the world. it really helps a lot!
- Sat Mar 06, 2021 10:03 am
- Forum: General Rate Laws
- Topic: a=1 in First Order Reactions
- Replies: 11
- Views: 725
Re: a=1 in First Order Reactions
It would depend on the stoichiometric coefficients. A would vary accordingly and doesn't always have to be 1.
- Sat Mar 06, 2021 10:01 am
- Forum: Zero Order Reactions
- Topic: 0 order
- Replies: 14
- Views: 1586
Re: 0 order
A zero order reaction means that the rate of reaction is independent of concentration of reactants.
https://www.toppr.com/ask/question/what ... e-example/
https://www.toppr.com/ask/question/what ... e-example/
- Sat Mar 06, 2021 9:56 am
- Forum: Student Social/Study Group
- Topic: 14B Final
- Replies: 22
- Views: 1137
Re: 14B Final
Last quarter, in Chem 14A, the final was equally cumulative. So, I guess studying all of the units will be really helpful on the Chem 14B final too!
- Sat Mar 06, 2021 9:54 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Video Review
- Replies: 8
- Views: 532
Re: Video Review
Same here! I used Organic Chemistry Tutor videos to prepare for the Midterms, and it really helped me understand the conceptual topics easily.
- Sat Mar 06, 2021 9:52 am
- Forum: Student Social/Study Group
- Topic: Playlist
- Replies: 86
- Views: 8913
Re: Playlist
Right now I have been listening to 'Folklore' by Taylor Swift on repeat!
- Sat Feb 27, 2021 8:09 am
- Forum: Student Social/Study Group
- Topic: Fave food
- Replies: 266
- Views: 47793
Re: Fave food
i am craving something spicy like Indian chaat!
- Sat Feb 27, 2021 8:07 am
- Forum: Balancing Redox Reactions
- Topic: Adding OH-
- Replies: 5
- Views: 414
Re: Adding OH-
If you have to balance the redox reaction which is taking place in a BASIC solutions, then we use OH- and H2O.
- Sat Feb 27, 2021 8:06 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Moles in ΔG = -nFE
- Replies: 45
- Views: 4318
Re: Moles in ΔG = -nFE
n represents the number of moles of electrons transferred in the balanced reaction.
- Sat Feb 27, 2021 8:05 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Spontaneity
- Replies: 2
- Views: 295
Re: Spontaneity
Yes. If E cell is positive, then G will be negative. Thus, the reaction will be spontaneous.
- Sat Feb 27, 2021 8:01 am
- Forum: Balancing Redox Reactions
- Topic: Acidic vs. Basic
- Replies: 20
- Views: 875
Re: Acidic vs. Basic
For acidic solutions, we use H+ and H2O to balance but in basic solutions we use OH- and H2O.
- Sun Feb 21, 2021 8:05 am
- Forum: Student Social/Study Group
- Topic: Classes for next quarter?
- Replies: 165
- Views: 20083
Re: Classes for next quarter?
I planning on taking Stats 10, Anthro 2, and Chem 14C if I get a spot!
- Sun Feb 21, 2021 8:04 am
- Forum: Student Social/Study Group
- Topic: Points needed to pass?
- Replies: 76
- Views: 10108
Re: Points needed to pass?
I think you need a C- to pass which means that you have to have 200 points for that.
- Sun Feb 21, 2021 8:03 am
- Forum: Student Social/Study Group
- Topic: Post Midterm 2 De-stressing
- Replies: 92
- Views: 8727
Re: Post Midterm 2 De-stressing
I have two midterms on Monday!! So, unfortunately i'll be chilling after that. There are a couple of Bollywood movies on my watchlist. I'm planning on watching at least two of them! :)
- Sun Feb 21, 2021 8:01 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gas Constant R
- Replies: 43
- Views: 4249
Re: Gas Constant R
The value of R which has to be used depends on the units: 8.314 J mol-1 K-1 or 0.08206 L.atm mol-1 K-1
Also, you don't have to remember these, just look it up on the equation sheet!
Also, you don't have to remember these, just look it up on the equation sheet!
- Sun Feb 21, 2021 7:57 am
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: confusion on using Cp and Cv
- Replies: 24
- Views: 1201
Re: confusion on using Cp and Cv
Cp is the heat capacity at constant pressure while Cv is the heat capacity at constant volume.
Also, Cp = Cv + R
Also, Cp = Cv + R
- Sun Feb 14, 2021 11:03 am
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: ΔS of system vs ΔS of surroundings
- Replies: 2
- Views: 204
Re: ΔS of system vs ΔS of surroundings
From what I understood from this week's sapling HW:
S of the system can be found by Sproducts - Sreactants
S of surroundings = -Hsystem/T
S of the system can be found by Sproducts - Sreactants
S of surroundings = -Hsystem/T
- Sun Feb 14, 2021 10:59 am
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Temperature Question
- Replies: 8
- Views: 524
Re: Temperature Question
The change in temperature in Celsius or kelvin is the same. So, you don't have to worry about units.
- Sun Feb 14, 2021 10:52 am
- Forum: General Science Questions
- Topic: conversions [ENDORSED]
- Replies: 6
- Views: 856
Re: conversions [ENDORSED]
While solving a problem, I think having all of the quantities in similar units is a must. So, I like to convert joules to kilojoules or vice-versa before starting the calculations so that it becomes easier to solve the problem without making mistakes.
- Sun Feb 14, 2021 10:49 am
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: delta G
- Replies: 9
- Views: 587
Re: delta G
delta G --> free energy change of a reaction
delta G knot --> free energy change of a reaction under standard conditions(like 1 atm, 298 K, 1M concentration)
delta G knot --> free energy change of a reaction under standard conditions(like 1 atm, 298 K, 1M concentration)
- Sun Feb 14, 2021 10:44 am
- Forum: Student Social/Study Group
- Topic: Valentine's Day Long Weekend!
- Replies: 30
- Views: 2309
Re: Valentine's Day Long Weekend!
Happy Valentine's Day everyone! Please don't forget to relax and recharge during the long weekend.
- Sun Feb 07, 2021 4:13 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Cp and Cv
- Replies: 7
- Views: 459
Re: Cp and Cv
I think Cp = Cv + R
- Sun Feb 07, 2021 4:11 pm
- Forum: Phase Changes & Related Calculations
- Topic: H and q
- Replies: 47
- Views: 1931
Re: H and q
Q --> heat
H --> enthalpy
H --> enthalpy
- Sun Feb 07, 2021 4:09 pm
- Forum: Ideal Gases
- Topic: R ideal gas constant
- Replies: 31
- Views: 2283
Re: R ideal gas constant
the different values of R just correspond to the different units. Just being aware of the units in the problem helps to know whether to use 8.314 or 0.0821 as the R value.
- Sun Feb 07, 2021 4:08 pm
- Forum: Student Social/Study Group
- Topic: Study routine.
- Replies: 51
- Views: 3067
Re: Study routine.
i think keeping up with the lectures as they are released has really helped me. Also doing textbook problems is a good way to practice other than sapling. Lastly, try to attend as many review sessions as possible.
- Sun Feb 07, 2021 4:04 pm
- Forum: Student Social/Study Group
- Topic: Book Recommendations
- Replies: 135
- Views: 19194
Re: Book Recommendations
The Language Instinct by Steven Pinker is really a cool book if you are interested in linguistics!
- Sun Feb 07, 2021 4:02 pm
- Forum: Student Social/Study Group
- Topic: Book Recommendations
- Replies: 135
- Views: 19194
Re: Book Recommendations
Sunny Wu 3A wrote:Chemical Principles: The Quest for Insight Seventh Edition by Atkins et al.
Just kidding, I second Crime and Punishment and Fahrenheit 451 :)
lol!
- Sun Feb 07, 2021 4:01 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Systems
- Replies: 24
- Views: 999
Re: Systems
universe is an isolated system because it literally contains everything and so there is no room for exchange with anything.
- Sat Jan 30, 2021 10:41 am
- Forum: General Science Questions
- Topic: MT 1 Grades
- Replies: 8
- Views: 489
Re: MT 1 Grades
I think it will take about a week or longer for the grades to be released(that was my experience last quarter in Chem 14A).
- Sat Jan 30, 2021 10:39 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Memorize bond enthalpies / standard enthalpies of formation?
- Replies: 39
- Views: 1507
Re: Memorize bond enthalpies / standard enthalpies of formation?
The values will be provided on exams just like we have them available while solving sapling or textbook problems!
- Sat Jan 30, 2021 10:37 am
- Forum: Phase Changes & Related Calculations
- Topic: endothermic/exothermic
- Replies: 43
- Views: 4950
Re: endothermic/exothermic
Endothermic reactions involve absorption of energy to break bonds. So, phase changes of solid to liquid, liquid to gas, and solid to gas will be endothermic reactions.
Exothermic reactions release energy during formation of bonds. So, the phase changes of liquid to solid, gas to liquid.
Exothermic reactions release energy during formation of bonds. So, the phase changes of liquid to solid, gas to liquid.
- Sat Jan 30, 2021 10:33 am
- Forum: Phase Changes & Related Calculations
- Topic: when to assume x is insignificant
- Replies: 86
- Views: 8950
Re: when to assume x is insignificant
I remember that Dr. Lavelle said in his lectures that whenever K is less than 10^-4. Also, you can always check it. If the value of x is less than 5% of the initial molarity, you are good to go!
- Sat Jan 30, 2021 10:31 am
- Forum: Student Social/Study Group
- Topic: Culinary Chemistry
- Replies: 239
- Views: 41499
Re: Culinary Chemistry
I was just reading about non-stove cooking and stumbled across a passage describing how marination not only imbibes food with extra flavor but also breaks down proteins in meat dishes - when the marinade contains an acidic element, as it usually does - essentially "cooking" it without req...
- Sat Jan 23, 2021 9:01 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Sapling week 2 #9
- Replies: 8
- Views: 447
Re: Sapling week 2 #9
Fiona Huang 3C wrote:Thank you guys! So is it the opposite for bases? When pH>pka, the neutral species would be predominant?
Yes! When pH>pka, neutral species would dominate and when pH<pka charged species dominate.
- Sat Jan 23, 2021 8:57 am
- Forum: Student Social/Study Group
- Topic: Logistics for the Midterm
- Replies: 11
- Views: 806
Re: Logistics for the Midterm
The first midterm is during our class on Friday so I think that it will be proctored like our final in Chem 14A.
- Sat Jan 23, 2021 8:55 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: ICE Tables
- Replies: 36
- Views: 2017
Re: ICE Tables
The C row or the change row is determined by the stoichiometric coefficients in the reaction equation.
For ex: H2 + Cl2 ---> 2HCl
In the forward reaction the change for H2 will be -x, for Cl2 will be -x, and HCl will be +2x(because of its coefficients).
For ex: H2 + Cl2 ---> 2HCl
In the forward reaction the change for H2 will be -x, for Cl2 will be -x, and HCl will be +2x(because of its coefficients).
- Sat Jan 23, 2021 8:51 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Studying for Midterm #1
- Replies: 63
- Views: 3173
Re: Studying for Midterm #1
Some things that helped me while doing Chem 14A with Dr. Lavelle last quarter:
1. Attending UA sessions
2. Reading the textbook
3. Doing the textbook problems
4. Revisiting the sapling HW problems
Hope this helps!
1. Attending UA sessions
2. Reading the textbook
3. Doing the textbook problems
4. Revisiting the sapling HW problems
Hope this helps!
- Sat Jan 23, 2021 8:48 am
- Forum: Student Social/Study Group
- Topic: Midterm Study Tips
- Replies: 41
- Views: 2114
Re: Midterm Study Tips
I think the some things that really helped me on the midterm in Chem 14A last quarter were attending the UA sessions and doing the textbook reading along with doing the textbook problems.
- Sat Jan 16, 2021 10:31 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: q vs k
- Replies: 62
- Views: 2977
Re: q vs k
Q and K are calculated in the same way but Q is the calculation that is not done at equilibrium.
- Sat Jan 16, 2021 10:29 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: H2O as a Gas
- Replies: 69
- Views: 7337
Re: H2O as a Gas
If H2O is a gas, you should include it in the ICE table!
- Sat Jan 16, 2021 10:28 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Sapling #5
- Replies: 5
- Views: 282
Re: Sapling #5
This problem can be solved in the way we solve simultaneous linear equations in algebra. So in this particular question, you will have to add the first reaction equation and the REVERSE of the third reaction equation. Also you might have multiply one of the equations by a constant and don't forget t...
- Sat Jan 16, 2021 10:24 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Le Chatelier's Principle
- Replies: 19
- Views: 1535
Re: Le Chatelier's Principle
Basically Le Chatelier's principle states that when a system experiences a disturbance (such as concentration, temperature, or pressure changes), it will respond to restore a new equilibrium state. For instance, if there is an increase in the concentration of products, the equilibrium will shift tow...
- Sat Jan 16, 2021 9:56 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Sapling #3
- Replies: 5
- Views: 353
Re: Sapling #3
I did the same mistake! The numerator should be 4x^2 and not 2x^2
- Sun Jan 10, 2021 5:35 pm
- Forum: Student Social/Study Group
- Topic: Study Habits
- Replies: 96
- Views: 8025
Re: Study Habits
I think the textbook questions helped me a lot. Also, the step-up sessions and workshops really help too! Being regular and keeping up with the lectures also help.
- Sun Jan 10, 2021 5:33 pm
- Forum: Student Social/Study Group
- Topic: Participation
- Replies: 56
- Views: 3472
Re: Participation
The points for participation can bee seen on your gradebook on ccle. But I don't think that they are updated regularly. Last quarter when I took chem 14A, it took about 3 weeks for the first set of participation points to be uploaded.
- Sun Jan 10, 2021 5:30 pm
- Forum: Student Social/Study Group
- Topic: Chemistry Community
- Replies: 29
- Views: 1493
Re: Chemistry Community
Jada3K wrote:Hopefully, someone sees this I was wondering if our chem community post carries over if we went over 50 from last quarter.
I don't think so Jada though I might be wrong!
- Sun Jan 10, 2021 5:30 pm
- Forum: Student Social/Study Group
- Topic: Chemistry Community
- Replies: 29
- Views: 1493
Re: Chemistry Community
The deadline for completing your 5 posts of the week is Sunday midnight!
- Sun Jan 10, 2021 5:26 pm
- Forum: General Science Questions
- Topic: midterm/final
- Replies: 12
- Views: 759
Re: midterm/final
I think it will. If you look at the syllabus on the chemistry 14B website, it says that midterms will be 50 minute long while the final will be 1 hour and 30 minutes long. It also says that both will be proctored, which is sounds exactly like chem 14A!
- Tue Jan 05, 2021 8:49 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3904281
Re: Post All Chemistry Jokes Here
i really liked this one!
- Thu Dec 10, 2020 6:22 pm
- Forum: Student Social/Study Group
- Topic: Anxiety
- Replies: 109
- Views: 9412
Re: Anxiety
Anxiety is normal. All of us want to do well and push ourselves to new limits. But I find that while trying to do well, I often forget the importance of taking breaks. It is crucial to step away from what you have been doing. As mentioned above a change of scenery really helps a lot! All the best! Y...
- Wed Dec 09, 2020 7:55 am
- Forum: Bronsted Acids & Bases
- Topic: HF
- Replies: 15
- Views: 929
Re: HF
HF is a weak acid as F is highly electronegative and does not readily give up proton.
- Wed Dec 09, 2020 7:25 am
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Sapling Q #1
- Replies: 7
- Views: 351
Re: Sapling Q #1
The above answer has included almost all the common strong acids. I think that strong bases include the oxides and hydroxides of both Group 1 and group 2 metals.
- Wed Dec 09, 2020 7:22 am
- Forum: Naming
- Topic: [Co(NH3)5 Cl] Cl 2H2O
- Replies: 5
- Views: 345
Re: [Co(NH3)5 Cl] Cl 2H2O
2H2O is named as dihydrate and not diaqua as it is not included in the coordination sphere.
- Wed Dec 09, 2020 7:20 am
- Forum: Bronsted Acids & Bases
- Topic: Amphoteric compounds
- Replies: 8
- Views: 621
Re: Amphoteric compounds
An amphoteric compound is one that can act as both an acid and a base. Basically, it can accept and lose protons.
- Thu Dec 03, 2020 5:29 am
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm 1 and 2 Review
- Replies: 8
- Views: 584
Re: Midterm 1 and 2 Review
I think that you can go to your TA's office hours for the review!
- Thu Dec 03, 2020 5:28 am
- Forum: Student Social/Study Group
- Topic: How are you?
- Replies: 154
- Views: 17377
Re: How are you?
I am just waiting for our finals to get over! The last couple of weeks have been really tiring though.
- Thu Dec 03, 2020 5:26 am
- Forum: Naming
- Topic: what does (en) mean?
- Replies: 23
- Views: 10627
Re: what does (en) mean?
en stands for ethylenediamine, which is a bidendate ligand.
- Thu Dec 03, 2020 5:23 am
- Forum: Hybridization
- Topic: Pi Bonds Cannot Rotate
- Replies: 29
- Views: 4307
Re: Pi Bonds Cannot Rotate
Pi-bonds overlap side-by-side. If they rotate, they will break. Hence, pi bonds do not rotate.
- Thu Dec 03, 2020 5:21 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Finding Coordination Number
- Replies: 14
- Views: 684
Re: Finding Coordination Number
The coordination number can be easily found by calculating the number of bonds formed by the central transition atom
- Fri Nov 27, 2020 3:39 am
- Forum: Hybridization
- Topic: Sp3d or dsp3
- Replies: 22
- Views: 2264
Re: Sp3d or dsp3
It's the same thing. I personally like to use the first one because it follows the order we are used to!
- Fri Nov 27, 2020 3:38 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: carbon hydrogen bonds
- Replies: 6
- Views: 405
Re: carbon hydrogen bonds
From what I understand, if the central atom has lone pairs only then we will see lone pairs affecting molecular geometry.
- Fri Nov 27, 2020 3:36 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Shape Names
- Replies: 50
- Views: 2696
Re: Shape Names
Yes, the shape of the water molecule is bent or angular.
- Fri Nov 27, 2020 3:35 am
- Forum: Hybridization
- Topic: Single Bonds and Sigma Bonds
- Replies: 23
- Views: 1226
Re: Single Bonds and Sigma Bonds
I think all bonds have atleast one sigma bonds and the rest are pi bonds.
- Fri Nov 27, 2020 3:33 am
- Forum: Student Social/Study Group
- Topic: How have your study habits changed?
- Replies: 45
- Views: 2248
Re: How have your study habits changed?
I like to understand the text as a go through it rather than blindly taking notes. Also, I think doing the textbook problems really helped me in the second midterm.
- Fri Nov 20, 2020 7:49 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Determining an orbital
- Replies: 10
- Views: 667
Re: Determining an orbital
'l' will determine which subshell it is: s, p, d, or f.
l=0 --> s
l=1 --> p
l=2 --> d
l=3 --> f
l=0 --> s
l=1 --> p
l=2 --> d
l=3 --> f
- Fri Nov 20, 2020 7:47 am
- Forum: Bond Lengths & Energies
- Topic: Boiling/Melting Point
- Replies: 29
- Views: 1388
Re: Boiling/Melting Point
You would look at the intermolecular forces. As the intramolecular forces don't contribute towards the melting/boiling points.
- Fri Nov 20, 2020 7:41 am
- Forum: Bond Lengths & Energies
- Topic: Bond Strength in DNA
- Replies: 12
- Views: 956
Re: Bond Strength in DNA
G-C bonds are stronger as they are triple bonds while A-T bonds are only double bonds. Due to larger bond strength, G-C bonds are more stable too.
- Fri Nov 20, 2020 7:38 am
- Forum: Dipole Moments
- Topic: Midterm 2 Results
- Replies: 7
- Views: 466
Re: Midterm 2 Results
I think they will be released sometime next week. As a couple of people mentioned above, they could be released sooner as there are no partial points this time.
- Fri Nov 20, 2020 7:37 am
- Forum: Student Social/Study Group
- Topic: grade worries
- Replies: 119
- Views: 24208
Re: grade worries
You are not alone! I am sure a lot of us(including me) are super stressed about grades. But just know that if you stress too much or put pressure on yourself, you won't be able to perform your best. So just chill!
- Thu Nov 12, 2020 8:29 am
- Forum: Sigma & Pi Bonds
- Topic: Triple bond?
- Replies: 21
- Views: 942
Re: Triple bond?
A triple bond has one sigma and one pi bond
Basically, multiple bonds have both sigma and pi bonds.
Basically, multiple bonds have both sigma and pi bonds.
- Thu Nov 12, 2020 8:25 am
- Forum: Formal Charge and Oxidation Numbers
- Topic: Oxidization Numbers
- Replies: 10
- Views: 625
Re: Oxidization Numbers
I don't think that we went over this in lectures, but as there is a homework question I assume that we need to know the basics. The link below really helped me!
https://www.thoughtco.com/rules-for-ass ... ers-607567
https://www.thoughtco.com/rules-for-ass ... ers-607567
- Thu Nov 12, 2020 8:07 am
- Forum: Bond Lengths & Energies
- Topic: Sapling HW Bond Length
- Replies: 7
- Views: 422
Re: Sapling HW Bond Length
I think you have interpreted the relationship between the atomic radius of O and S incorrectly. S has a larger atomic radius as atomic radii increases down the group.
- Thu Nov 12, 2020 8:01 am
- Forum: General Science Questions
- Topic: Which would have lower ionization energy?
- Replies: 13
- Views: 808
Re: Which would have lower ionization energy?
Chlorine will have lower ionization energy. This is so as it is one period below oxygen and so its electrons will be less tightly held.
- Thu Nov 12, 2020 7:58 am
- Forum: Lewis Structures
- Topic: Formal Charge
- Replies: 5
- Views: 228
Re: Formal Charge
I don't think that it is necessary to find the formal charge every time, but it certainly helps in checking your work. It could also help in calculating the formal charge of the central atom without many calculations. Like in the last week's lecture, Lavelle used the formal charges along with the ov...
- Fri Nov 06, 2020 8:24 pm
- Forum: Resonance Structures
- Topic: Bond lengths
- Replies: 20
- Views: 787
Re: Bond lengths
I don't think that we actually have to draw the double bonds shorter. Knowing that double bonds are shorter is enough!
- Fri Nov 06, 2020 8:22 pm
- Forum: *Shrodinger Equation
- Topic: Electron Density
- Replies: 3
- Views: 282
Re: Electron Density
Electron density is just the probability of an electron being present.
The electron density or the probability of finding electrons in a nodal plane is zero.
The electron density or the probability of finding electrons in a nodal plane is zero.
- Fri Nov 06, 2020 8:19 pm
- Forum: Student Social/Study Group
- Topic: Blind sided by Midterm 1 memorization questions, How to study for memorization questions
- Replies: 11
- Views: 433
Re: Blind sided by Midterm 1 memorization questions, How to study for memorization questions
I personally did not expect memorization problems on the midterm, but my previous knowledge helped me there. I think what you did in terms of preparing for the first midterm is perfect. Instead of skimming over the memorization based topics, make notes on them. Usually, memorization topics include t...
- Fri Nov 06, 2020 8:12 pm
- Forum: Octet Exceptions
- Topic: Phosphorus and d-Orbital
- Replies: 7
- Views: 373
Re: Phosphorus and d-Orbital
I think I need to first understand the octet rule, can anyone help with that? The octet rule refers to the tendency of atoms preferring to have eight electrons in the valence shell. Basically, the tendency of elements to have the electronic configuration of the nearest noble gas(which has fully fil...
- Fri Nov 06, 2020 8:07 pm
- Forum: Properties of Light
- Topic: Photoelectric Effect
- Replies: 14
- Views: 933
Re: Photoelectric Effect
Yes, it is the same thing.
We know, kinetic energy = energy of incident light - threshold energy. Thus, it is evident from the equation that the excess energy corresponds to kinetic energy
We know, kinetic energy = energy of incident light - threshold energy. Thus, it is evident from the equation that the excess energy corresponds to kinetic energy
- Fri Nov 06, 2020 8:03 pm
- Forum: Ionic & Covalent Bonds
- Topic: Atomic Radius
- Replies: 38
- Views: 3285
Re: Atomic Radius
All the elements in a period have the same number of shells(just the number of valence electrons vary). But, the number of protons across a period increases, and so the effective nuclear charge increases which causes the size to decrease across a period.
- Sun Nov 01, 2020 3:13 am
- Forum: Student Social/Study Group
- Topic: Halloween!!!
- Replies: 73
- Views: 4322
Re: Halloween!!!
Happy Halloween!
I watched my missed chemistry lectures and The Mandalorian simultaneously while gorging on the pumpkin choco-chip cookies I baked!
I watched my missed chemistry lectures and The Mandalorian simultaneously while gorging on the pumpkin choco-chip cookies I baked!
- Sun Nov 01, 2020 3:07 am
- Forum: Trends in The Periodic Table
- Topic: Atomic Radius
- Replies: 30
- Views: 3220
Re: Atomic Radius
The atomic radius depends upon the effective nuclear charge and number of shells. Across a period, the nuclear charge increases, and the number of shells remain the same, so the size decreases. However down the group, though both the effective nuclear charge and the number of shells increases, the m...
- Sun Nov 01, 2020 3:02 am
- Forum: Properties of Light
- Topic: Is c always the speed of light?
- Replies: 92
- Views: 6479
Re: Is c always the speed of light?
This class requires us to know c as the speed light which is 3 X 10^8 m/s
- Wed Oct 28, 2020 10:39 pm
- Forum: Student Social/Study Group
- Topic: Lavelle's Jokes
- Replies: 26
- Views: 2424
Re: Lavelle's Jokes
I really liked this one!
- Wed Oct 28, 2020 10:30 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: 3d and 4s orbitals
- Replies: 9
- Views: 376
Re: 3d and 4s orbitals
I personally like to use the Aufbau principle that states that in the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels. The arrows in the figure really help to determine which comes first.
- Wed Oct 28, 2020 10:27 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: 4s and 3d
- Replies: 14
- Views: 513
Re: 4s and 3d
I think that's because of the Aufbau principle which states that in the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels.
- Tue Oct 20, 2020 11:04 pm
- Forum: Properties of Electrons
- Topic: 1A.1
- Replies: 1
- Views: 125
Re: 1A.1
All light(EM radiations) travel at the same speed, i.e approx 3 X 10^8 m/s. But as the observed speed is LESS THAN the speed of light, it supports the particle model. Hope it helps!
- Tue Oct 20, 2020 10:52 pm
- Forum: Photoelectric Effect
- Topic: Photoelectric Experiment
- Replies: 6
- Views: 255
Re: Photoelectric Experiment
The photoelectric experiment can only give accurate results under vacuum. If not conducted in a vacuum, the ejected electrons can collide with the particles present in the air and interfere with the data.
- Tue Oct 20, 2020 10:46 pm
- Forum: Properties of Light
- Topic: Difference between E=hv and E=hc/v?
- Replies: 9
- Views: 8912
Re: Difference between E=hv and E=hc/v?
I think you meant to ask the difference between E = hv and E= hc/λ. They are essentially the same thing.
We know, c = λv
=> v = c/λ --- equation 1
So, E = hv
=> E = hc/λ (from equation 1)
Hope it helps!
We know, c = λv
=> v = c/λ --- equation 1
So, E = hv
=> E = hc/λ (from equation 1)
Hope it helps!
- Tue Oct 20, 2020 10:42 pm
- Forum: Properties of Light
- Topic: Planck's Constant
- Replies: 7
- Views: 312
Re: Planck's Constant
As stated in the previous responses, Planck's constant(h) = 6.626 X 10^(-34). I had trouble remembering its value earlier, but as I started doing the textbook questions in the syllabus, I realized that it was being used regularly. So, the repeated usage has permanently etched the value in my head! B...
- Tue Oct 20, 2020 10:37 pm
- Forum: Student Social/Study Group
- Topic: How are you studying?
- Replies: 204
- Views: 25317
Re: How are you studying?
I first go through all the pre-modules. Even though they are a bit lengthy and take up a lot of time, they are really useful. Then I watch the lectures and take notes on the topics that I might have not understood in the pre-modules. Then I do the textbook questions given in the syllabus - THEY ARE ...
- Tue Oct 13, 2020 10:27 pm
- Forum: Balancing Chemical Reactions
- Topic: Naming compounds
- Replies: 21
- Views: 1424
Re: Naming compounds
The majority of the compound names will be given on the test. But, it is always helpful to know the compounds that occur repeatedly like CO2, H20 (as someone already mentioned above).
I found this really helpful link : https://youtu.be/ptAw20kem90
I found this really helpful link : https://youtu.be/ptAw20kem90
- Tue Oct 13, 2020 10:22 pm
- Forum: Empirical & Molecular Formulas
- Topic: Sapling Week 1 #8
- Replies: 23
- Views: 1505
Re: Sapling Week 1 #8
The molecular formula can be determined from the figure simply by counting the number of atoms of each element in the compound. For instance, you can figure out that the compound has three elements: C, O, and H. Now just count the number of C, H, and O. That will be your molecular formula: C6H8O6. T...
- Tue Oct 13, 2020 10:13 pm
- Forum: Balancing Chemical Reactions
- Topic: Balancing Chemical Equations
- Replies: 11
- Views: 669
Re: Balancing Chemical Equations
CO4 will mean that C=1 and O=4. However, if the compound had been (CO)4, it would have meant that C=4 and O=4. Usually, the parentheses(if present) around the atoms of the compound will help you to determine the number of those atoms.
- Tue Oct 13, 2020 10:07 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: mmol
- Replies: 14
- Views: 1631
Re: mmol
Whenever you see 'm', it implies 'milli'. So, the unit mmol means millimolar. Also, milli corresponds to 10^(-3).
- Tue Oct 13, 2020 10:04 pm
- Forum: Significant Figures
- Topic: Sapling HW #4
- Replies: 31
- Views: 2031
Re: Sapling HW #4
950000 has only two significant figures as all the trailing zeroes to the non-zero numbers are NOT SIGNIFICANT
80060 has 4 significant figures as the zeroes between two non zero numbers are significant. The last zero won't be significant as trailing zeroes to any non-zero number isn't significant.
80060 has 4 significant figures as the zeroes between two non zero numbers are significant. The last zero won't be significant as trailing zeroes to any non-zero number isn't significant.