Search found 35 matches

by Keerthana Sivathasan 4G
Thu Nov 14, 2019 6:25 am
Forum: Student Social/Study Group
Topic: Final Exam
Replies: 10
Views: 45

Re: Final Exam

Yes, the final exam is cumulative and will cover material from Weeks 1-10.
by Keerthana Sivathasan 4G
Thu Nov 14, 2019 6:22 am
Forum: Administrative Questions and Class Announcements
Topic: Test topics
Replies: 5
Views: 32

Re: Test topics

If you go under the Test #2 Forum, someone had mentioned that their TA said Test 2 will cover the topics of "VSEPR, IMF, polarity and bonding".
by Keerthana Sivathasan 4G
Thu Nov 14, 2019 6:20 am
Forum: Administrative Questions and Class Announcements
Topic: 14BL
Replies: 5
Views: 51

Re: 14BL

Most people take 14BL after fully finishing 14A and 14B, so they could already have a good grasp on the concepts covered in lab. 14BL does require a lot of work, so I wouldn't recommend taking it with 3 other classes, especially if your other classes are also work heavy and time consuming.
by Keerthana Sivathasan 4G
Thu Nov 14, 2019 6:17 am
Forum: Administrative Questions and Class Announcements
Topic: Homework for week 7
Replies: 3
Views: 32

Re: Homework for week 7

I think homework from chapter 3F would be perfect, especially because we didn't start Molecular Shape and Structure until yesterday in lecture and some people would have already had discussion this week.
by Keerthana Sivathasan 4G
Wed Nov 13, 2019 8:24 pm
Forum: *Liquid Structure (Viscosity, Surface Tension, Liquid Crystals, Ionic Liquids)
Topic: Viscosity
Replies: 12
Views: 50

Re: Viscosity

Viscosity is the measure of resistance of a fluid to flow. A fluid that is highly viscous has a high resistance (like having more friction) and flows slower than a low-viscosity fluid. The easier a fluid moves, the lower the viscosity. Viscosity is expressed in units of the poise (mPa•s). Because a ...
by Keerthana Sivathasan 4G
Thu Nov 07, 2019 3:03 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VESPR
Replies: 5
Views: 27

Re: VESPR

VSEPR will be covered in 2E, but we were only tested on the midterm until 2D, so we won't be expected to know it yet, as he also hasn't mentioned it in class.
by Keerthana Sivathasan 4G
Thu Nov 07, 2019 3:01 pm
Forum: SI Units, Unit Conversions
Topic: Kj
Replies: 6
Views: 25

Re: Kj

Kilo is always 10^3. Other prefixes include Mega (10^6), Deci (10^-1), Centi (10^-2), Milli (10^-3), Micro (10^-6), Nano (10^-9), Pico (10^-12).
by Keerthana Sivathasan 4G
Thu Nov 07, 2019 2:57 pm
Forum: Lewis Structures
Topic: When to draw Resonance Structures
Replies: 14
Views: 64

Re: When to draw Resonance Structures

I'm pretty sure we will be asked to specifically draw resonance structures if he wishes we include them.
by Keerthana Sivathasan 4G
Thu Nov 07, 2019 2:45 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: HW 2D.3
Replies: 5
Views: 39

Re: HW 2D.3

BaBr2 is primarily ionic because the electronegativity difference between the Ba and Br molecules are high and using the scale ,<1.5 covalent , 1.5-2 polar covalent, 2< ionic, you can see from the Pauling Electronegativity table that BaBr2 is ionic with the differences in these 2 molecules electrone...
by Keerthana Sivathasan 4G
Thu Nov 07, 2019 2:29 pm
Forum: Electronegativity
Topic: Electronegativity Chart
Replies: 5
Views: 39

Re: Electronegativity Chart

We will not be given an electronegativity chart, but we won't need to know them very accurately or precisely. You just need to know whether it increases or decreases down a period and down a group, similar to how you should know the trends of ionization energy, electron affinity, and atomic radius.
by Keerthana Sivathasan 4G
Thu Oct 31, 2019 10:38 pm
Forum: Administrative Questions and Class Announcements
Topic: Do Midterm Review Sessions Repeat Topics?
Replies: 4
Views: 28

Re: Do Midterm Review Sessions Repeat Topics?

The topics are separated into sections-Fundamentals, Early Quantum, Late Quantum, Bonding/Structures. All the people in charge of, for example, Early Quantum, will cover the same topics like Electromagnetic Radiation, Photoelectric Effect, Atomic Spectra, and etc., but each will have a different app...
by Keerthana Sivathasan 4G
Thu Oct 31, 2019 10:27 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Formal Charge
Replies: 7
Views: 60

Re: Formal Charge

Formal charge also helps you determine whether you should leave a lone pair alone or make a double bond. Normally you would prefer a formal charge of 0, to make it the most stable.
by Keerthana Sivathasan 4G
Thu Oct 31, 2019 10:20 pm
Forum: Administrative Questions and Class Announcements
Topic: Advice on Homework
Replies: 13
Views: 119

Re: Advice on Homework

In terms of preparation for the midterm, I definitely think it will be helpful to do all the problems, because one of them will appear on our midterm, but in general, for our homework, you only need to do 5 to get full points.
by Keerthana Sivathasan 4G
Thu Oct 31, 2019 10:09 pm
Forum: Ionic & Covalent Bonds
Topic: Midterm
Replies: 28
Views: 149

Re: Midterm

The midterm will cover Fundamentals (Review of Chemical & Physical Principles), The Quantum World, and Chemical Bonds (excluding 3F.4 and 3F.5). We will be tested on material up to this Friday, November 1, 2019. Regarding electronegativity, I think we just need to know the general trends, not sp...
by Keerthana Sivathasan 4G
Thu Oct 31, 2019 9:46 pm
Forum: Administrative Questions and Class Announcements
Topic: 10/28 Updates due to Fire [ENDORSED]
Replies: 14
Views: 524

Re: 10/28 Updates due to Fire [ENDORSED]

On the Chemistry website, if you look on the right side under the header "Exam Information", there is a link labelled "Midterm Review Sessions and Rooms". Here you can find information about when and where the Midterm will take place, midterm review sessions, UA hours, and TA hou...
by Keerthana Sivathasan 4G
Mon Oct 21, 2019 12:52 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Kinetic Energy
Replies: 4
Views: 28

Re: Kinetic Energy

Instead use E(kinetic)=hf-(work function) to see when kinetic energy is equal to 0.
by Keerthana Sivathasan 4G
Mon Oct 21, 2019 12:50 pm
Forum: Quantum Numbers and The H-Atom
Topic: Balmer and Lyman Series
Replies: 6
Views: 39

Re: Balmer and Lyman Series

The Balmer and Lyman series relate to hydrogen. The emission spectrum of atomic hydrogen consists of particular wavelengths, which was discovered by Johann Jakob Balmer, a Swiss schoolteacher in 1853. He found that the visible wavelengths fit a mathematical formula. These wavelengths known as the Ba...
by Keerthana Sivathasan 4G
Mon Oct 21, 2019 12:21 pm
Forum: Photoelectric Effect
Topic: The Work Function
Replies: 15
Views: 71

Re: The Work Function

E=hv is not equal to the work function, but E(kinetic)=hv-(work function) is the equation you should use for the photoelectric effect. Hv is the energy of the photon coming in and shining on the metal, work function is the energy it takes for an electron to be emitted off a specific metal, and kinet...
by Keerthana Sivathasan 4G
Mon Oct 21, 2019 12:01 pm
Forum: Student Social/Study Group
Topic: Week 4 HW Problems
Replies: 7
Views: 65

Re: Week 4 HW Problems

I believe Quantum World is fine for Week 4 homework, as we haven't gone in to much depth for Chemical Bonds, and I'm sure even if you did one or the other, the TA will not mark points off because they are recently covered chapters.
by Keerthana Sivathasan 4G
Mon Oct 21, 2019 11:27 am
Forum: Administrative Questions and Class Announcements
Topic: Accessing the E-textbook [ENDORSED]
Replies: 19
Views: 348

Re: Accessing the E-textbook [ENDORSED]

Sapling isn't mandatory, but Professor Lavelle has put "multiple additional assignments and learning objectives for those who need additional assistance" which will definitely help you in any way possible, especially if you are struggling with a specific topic and may not be able to make i...
by Keerthana Sivathasan 4G
Mon Oct 14, 2019 5:28 pm
Forum: Administrative Questions and Class Announcements
Topic: Periodic Table on the Test
Replies: 7
Views: 57

Re: Periodic Table on the Test

I'm pretty sure they will provide us with the periodic table and needed formulas and equations. If we were allowed to bring our own periodic table, they would need to check everyone's to make sure no one is writing hints or clues on the back, which Is quite a hassle.
by Keerthana Sivathasan 4G
Mon Oct 14, 2019 5:24 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Test 1 [ENDORSED]
Replies: 107
Views: 1884

Re: Test 1 [ENDORSED]

Test 1 was worth 50 points and we don't bring anything. The TA provided us with the formula sheet and problems with much room, especially with the empty back sides to show work. We have the whole discussion section (50 minute period) to complete it. I think we will get it back by the next discussion...
by Keerthana Sivathasan 4G
Mon Oct 14, 2019 5:05 pm
Forum: Properties of Light
Topic: What is Threshold Energy?
Replies: 9
Views: 41

Re: What is Threshold Energy?

Threshold energy is the work function. We need to know this because it's different for each metal surface, and you have to know what the minimum energy required to make an electron fire off the surface would be. Another thing to note is that the number of electrons emitted of the metal surface depen...
by Keerthana Sivathasan 4G
Mon Oct 14, 2019 4:50 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Indeterminancy In Class
Replies: 7
Views: 30

Re: Indeterminancy In Class

In class today, he gave examples and explained more about the Heisenberg's Indeterminacy Equation. He also said we don't need to know how to derive it, because it's past the scope of our class.
by Keerthana Sivathasan 4G
Mon Oct 14, 2019 4:39 pm
Forum: Photoelectric Effect
Topic: frequency and speed
Replies: 7
Views: 37

Re: frequency and speed

Speed of radiation does not decrease when frequency decreases because it is a constant. Using the formula c=v*wavelength where v is frequency and c is speed, if v increases, then wavelength will decrease in order to maintain the same c. The variable c can't change because it is a constant.
by Keerthana Sivathasan 4G
Sun Oct 13, 2019 4:37 pm
Forum: DeBroglie Equation
Topic: When to use DeBroglie Equation
Replies: 16
Views: 104

Re: When to use DeBroglie Equation

DeBroglie is used for all moving particles and is a link between matter having wave properties and vice versa. The higher the energy, the lower the DeBroglie wavelength. All the moving particles must have a "matter wave", which is a probability function, associated with them.
by Keerthana Sivathasan 4G
Sun Oct 13, 2019 4:07 pm
Forum: Administrative Questions and Class Announcements
Topic: Week 2 Homework Problems [ENDORSED]
Replies: 67
Views: 1065

Re: Week 2 Homework Problems [ENDORSED]

Week 2 homework could be quantum and fundamentals solely because we also had Test 1 that week, and Lavelle said doing fundamentals problems for our homework would help us for the test, but because we learned some quantum in class, it was okay to do those problems as well.
by Keerthana Sivathasan 4G
Sun Oct 13, 2019 3:56 pm
Forum: Student Social/Study Group
Topic: Chemistry News
Replies: 61
Views: 37117

Re: Chemistry News

https://www.sciencedaily.com/releases/2 ... 095927.htm
I thought this article was interesting especially considering the big focus on climate change and ocean pollution now.
by Keerthana Sivathasan 4G
Sun Oct 13, 2019 3:40 pm
Forum: Administrative Questions and Class Announcements
Topic: Advice from a Medical Student - Part II [ENDORSED]
Replies: 117
Views: 1707

Re: Advice from a Medical Student - Part II [ENDORSED]

Hearing your story makes me so happy! Congratulations on everything you have achieved so far and everything you are going to in the future. Pediatrics is my desired specialty, so I'm so happy you find it so enjoyable. I think it's interesting to go through rotations in several different specialties ...
by Keerthana Sivathasan 4G
Sun Oct 13, 2019 3:31 pm
Forum: General Science Questions
Topic: Rusty on High School Chem [ENDORSED]
Replies: 166
Views: 100970

Re: Rusty on High School Chem [ENDORSED]

I have a similar experience taking chemistry sophomore year of high school, and now doing 14A is difficult. I definitely do feel that Lavelle does give us the most resources that he can with all the outside hours by UA and TA and obviously his office hours, which we have to utilize for most success....
by Keerthana Sivathasan 4G
Fri Oct 04, 2019 9:07 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Homework Grading
Replies: 7
Views: 48

Re: Homework Grading

In terms of rounding for the homework, I remember Professor Lavelle mentioning to not round any answers until the end to obtain the most accurate answer, and for the final answer as long as we keep the same number of sig figs, I think we will be good. I don't think we will be penalized for not writi...
by Keerthana Sivathasan 4G
Fri Oct 04, 2019 8:56 pm
Forum: Significant Figures
Topic: Sig Figs
Replies: 3
Views: 36

Re: Sig Figs

For better reference, here are some more rules: 1. Non zero digits are always significant. 2. Zeros between 2 significant digits are significant. 3. Trailing zeros and final zero are only significant in the decimal part. 4. For numbers less than 1 like in 0.05, the 0 before the decimal point is sign...
by Keerthana Sivathasan 4G
Fri Oct 04, 2019 8:35 pm
Forum: Administrative Questions and Class Announcements
Topic: Saying Thank You to Dr. Lavelle
Replies: 209
Views: 101157

Re: Saying Thank You to Dr. Lavelle

Dear Professor, I truly appreciate the way that you are always so positive and smile a lot during class, which makes chem go by so fast, especially because sometimes these concepts may be difficult to understand and grasp. I also find it so nice that you give out so many opportunities to get help, l...
by Keerthana Sivathasan 4G
Fri Oct 04, 2019 8:29 pm
Forum: Student Social/Study Group
Topic: Final Jitters
Replies: 63
Views: 18515

Re: Final Jitters

I personally feel the same way, but I have found several ways to help lessen my anxiety before finals. I always make sure to take breaks in between topics so my mind won't feel so crammed with information, and I like to start studying a little bit in advance to spread out the work. I also make sure ...
by Keerthana Sivathasan 4G
Fri Oct 04, 2019 8:16 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7606
Views: 1019065

Re: Post All Chemistry Jokes Here

What do you do with a sick chemist? If you can't helium, and you can't curium, then you might as well barium. The optimist sees the glass half full. The pessimist sees the glass half empty. The chemist see the glass completely full, half in the liquid state and half in the vapor state. Old chemists ...

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