CHEMISTRY COMMUNITY

Kirsten Yu 2K

Hi! Just to add on/clarify, the each equation works out to give you a straight line (y=mx+b) graph for its respective order. If you're working with a zero order reaction, the zero order equation will graph as coordinates forming a straight line, but if you plug the same values into the first or seco...

Kirsten Yu 2K

Hi! The steps I use to balance redox reactions in basic solution are below. Additional steps that are needed specifically for working with basic, rather than acidic, solutions are denoted with an asterisk. 1. Divide the RXN into 1/2RXNs 2. Balance the elements other than H and O 3. Balance the O ato...

Kirsten Yu 2K

Hi! Just to add on to the above points, the purpose of the salt bridge is that it prevents ions from building up, which allows the reactions in galvanic cells to carry out properly.

Kirsten Yu 2K

ln --> log base e
log --> log base 10
Hope this helps!

Kirsten Yu 2K

Hi! You can usually tell what measure of temperature to use (Celsius vs. Kelvin) by the context of the problem/the expected units for the answer. However, you can technically use either one as long as the proper conversions are done to complete the problem!

Kirsten Yu 2K

Zero work is done when volume is constant

Kirsten Yu 2K

E^o cell is used to describe when the cell is under standard conditions (1 atm and at a concentration of 1M). On the other hand, E cell is used when these conditions are not met. Hope this helps!

Kirsten Yu 2K

As mentioned above, your steps for the problem were all correct except for adding an extra zero to the value 0.0592! Once you adjust for that, you should get the correct answer

Kirsten Yu 2K

Technically, you don't have to write out the half-reactions every time to calculate the moles of electrons transferred, but it's helpful to make a habit of it with simpler reactions, because you'll need it for the more complex ones!

Kirsten Yu 2K

I thought this was a super interesting question, especially since there's no one ingredient in foundation that causes it to oxidize! It's actually caused by your makeup combining with the oils that are in your skin. That's why some people favor silicone-based primers, since they act as a sort of bar...

Kirsten Yu 2K

I would convert to moles. I've found that doing so significantly helps to reduce my number of silly calculation errors

Kirsten Yu 2K

I'm not sure-- I think there were curves given when classes were moved online due to covid, but now (to my understanding) the only curves are for grade cutoffs

Kirsten Yu 2K

I used to have a lot of post-exam stress, but what I realized is that once you've completed and turned in the exam, it's officially out of your hands. You've already done what you can, so there's no use wasting your time/energy/mental wellbeing stressing over how you did. Once you let it go, you'll ...

Kirsten Yu 2K

Great post! Thanks for making everyone feel a little bit better :)

Kirsten Yu 2K

If you want a snack you can mindlessly munch on, I recommend TJ's Crunchy Curls. Other than that, you can never go wrong with their Takis

Kirsten Yu 2K

It's definitely tough! Personally, on days where I have shorter shifts, I set aside a couple of hours for studying, but on days where I'm scheduled to work 7-8 hours, I give myself a pass and allot extra time for studying on the days I have off. It can be tough managing week-to-week, so I try to pla...

Kirsten Yu 2K

Textbook answers can be found at the end of the textbook (Back Matter > Odd-Numbered Exercises), but if you're looking for explanations as well you can find them linked under the textbook on Bruinlearn. Hope this helps!!!

Kirsten Yu 2K

I did all the textbook problems on the syllabus as prep for MT1 and MT2 and found those to be beneficial, but the review sessions seem really helpful so I'm planning on attending those before the final

Kirsten Yu 2K

Smino (blkswn), Mac Miller (Circles), and anything by Kali Uchis or Umi are my go-tos for chill study music

Kirsten Yu 2K

Brazilian BBQ! But definitely wishing I had fresh fruit to snack on rn

Kirsten Yu 2K

I definitely prepared for this midterm better than the first one, so I'm feeling more hopeful about it, but definitely nervous for grades to be posted next week!

Kirsten Yu 2K

The Audio-Visual Focus-Topics are super helpful if you're feeling rusty. Don't worry, you're not the only one--I took 14a last fall, and before that, the last time I learned chemistry before that was my sophomore year of high school

Kirsten Yu 2K

Interesting + quick read!
https://phys.org/news/2023-02-multiple- ... ental.html

Kirsten Yu 2K

I'm a fan of the sculpture garden, the botanical garden, and janss!

Kirsten Yu 2K

I've tried most of the coffee shops in Westwood, and my favorites (for both coffee and ambiance) have been Profeta and Ministry of Coffee. Both have a good amount of seating and there's usually other people working on assignments too. Warning for Profeta--they don't have any outlets that are availab...

Kirsten Yu 2K

To my knowledge, the 3 weekly Chem Community posts are due every Sunday at midnight (same as achieve!)

Kirsten Yu 2K

Hi! I attend the in-person lectures for this class, but what I've found to be helpful for my asynchronous classes is setting a specific time to watch the lectures. This helps maintain a sense of consistency and makes the lecture videos feel like a part of my daily routine. Hope this helps!

Kirsten Yu 2K

You don't have to make a new account, but make sure to update your information with your new discussion section!

Kirsten Yu 2K

I had this happen to me last fall when I took 14A, and what worked for me was closing the Lockdown browser and restarting it. For context, I have a MacBook, but this should work on any Windows device as well. Hope this helps!

Kirsten Yu 2K

Usually I click "Quick Links" (located in the upper left hand corner of the screen, just under the Chemistry Community header) and then "Your Posts". However, you can also just type your username into the search bar to find your posts.

Kirsten Yu 2K

To my knowledge, you are correct, we will not be tested on this.

Kirsten Yu 2K

Hi! Yes, the delta symbol represents the amount of "change" or "difference". As stated above, that means the delta value should always be a positive number.

Kirsten Yu 2K

multiply the number of meters by 10^9 to convert to nanometers

Kirsten Yu 2K

I believe the simplest solution is to multiply by the denominator!

Kirsten Yu 2K

Hi! In addition to M1V1 = M2V2, there's also m = n/v
m= molar concentration
n= moles of solute
v= liters of solution

Kirsten Yu 2K

EvaHeinrichs3C wrote:what is "angular momentum"?

The formula to calculate angular momentum is (L) = mvr, where m = mass, v = velocity, and r = radius.

Kirsten Yu 2K

Thank you so much for doing this! You are appreciated :)

Kirsten Yu 2K

Blackbody radiation refers to the spectrum of light emitted by any heated object. Further, a blackbody is a theoretical or model body that absorbs all radiation falling on it, reflecting/transmitting none.

Kirsten Yu 2K

Yes, after plugging in variables you should be able to end up with the kinetic energy equation.

Kirsten Yu 2K

The empirical formula shows the simplest (whole) number ratio of elements. Conversely, the molecular formula shows the actual ratio of elements in a given compound.

Kirsten Yu 2K

JohnathanH14 wrote:Did anyone happen to know where if we can find some of the even problem answers in the book?

To my knowledge, the textbook does not contain answers to even-numbered exercises.

Kirsten Yu 2K

pH formula: -log[H+]. As others have already mentioned, I don't think we need to know how to derive it, but it definitely wouldn't hurt to have as background knowledge.

Kirsten Yu 2K

Hi! We don't need to memorize the name or the symbol of elements on the periodic table. As others have mentioned, we are permitted to use a periodic table on both midterms and the final.

Kirsten Yu 2K

accuracy = closeness to the true value

Kirsten Yu 2K

Using the information given in the problem, you can deduce that there is one carbon, one oxygen, and four hydrogen atoms (empirical/molecular formula: CH4O). To draw the lewis structure, start by connecting the carbon and oxygen with a single bond. Then, connect two hydrogens to each of them, again ...

Kirsten Yu 2K

Doing the textbook problems given on the syllabus is the most helpful study method for me. I'd also recommend reviewing the online modules.

Kirsten Yu 2K

As others have already stated, ionization energy increases across periods and decreases down groups. Another way to think of it is that metals tend to have low ionization energies.

Kirsten Yu 2K

Yes, that is a good way of putting it. Atoms with a larger radius will have lower electronegativity because the attraction between electrons has an inversely proportional relationship to the size of the radius.

Kirsten Yu 2K

Hi, since I2 is a larger molecule than Cl2, it has greater polarizability. Greater polarizability means stronger London dispersion forces, which directly correlates to a higher boiling point (since both molecules are nonpolar, London dispersion forces are the only IMF present).

Kirsten Yu 2K

Negative formal charge indicates an extra electron. Conversely, positive formal charge indicates a missing electron.

Kirsten Yu 2K

Hi! Because of the octet rule and the fact that CO only has 10 electrons in total, the only way to draw the Lewis structure is with a triple bond (and one lone pair on each atom). To avoid confusion, I usually draw the Lewis structure first, then calculate formal charges after.

Kirsten Yu 2K

First, click on "quick links" in the upper left-hand corner. Then click on "my posts", which should be the first option in the drop-down menu. Hope this helps!

Kirsten Yu 2K

From what I understand, you only need 200/400 points in the class to get a C-. However, if you are looking to earn a B- or better, then the grading scale is "normal". For example, to get a B-, at the very least you would need a 320/400.

Kirsten Yu 2K

Aside from thorough studying, I think it's really essential to get a good night of sleep. I find myself in a much better headspace right before a test when I've gotten a full 8 hours of rest (especially as someone who doesn't sleep much on a regular basis).

Kirsten Yu 2K

Happy birthday, Professor! Hope you had an amazing day, you deserve it :)

Kirsten Yu 2K

Since we get to use the periodic table (and equation sheet) on both midterms/the final, we don't need to memorize the name or symbol of any of the elements!

Kirsten Yu 2K

I found this class's syllabus to be more vague than the other classes I'm enrolled in, from a timeline perspective. Some of my other professors have class-to-class outlines provided to give a sense of the pace of the course. However, I think Professor Lavelle's syllabus is extremely detailed in term...

Kirsten Yu 2K

Here's an interesting read on some recent developments regarding Einsteinium: https://www.nytimes.com/2021/02/07/scie ... ments.html

Kirsten Yu 2K

To my knowledge, AAP, Step Up, and Alpha Chi Sigma are all really helpful resources.

Kirsten Yu 2K

Two chemists walk into a bar. One says, “I’ll have an ‎H2O.” The other says, “I’ll have an ‎H2O, too.” The second chemist dies.

Kirsten Yu 2K

I try to maintain the number of sig figs initially established in the question, but rounding to 3 is usually a safe bet.

Kirsten Yu 2K

Hund’s rule: due to e- repulsion, e- in the same subshell occupy different orbitals with parallel spin (lowest energy)

Kirsten Yu 2K

In the quest to eliminate invasive glucose monitoring for people with diabetes, research led by Wenyu Gao, a Ph.D. student in the Department of Chemistry at the University of Waterloo, explores using saliva instead of blood to monitor glucose levels. Read here: brehttps://phys.org/news/2021-10-non-i...

Kirsten Yu 2K

Even though it feels tedious to get through at times, I highly value reading the textbook. It comes in handy when I'm looking into concepts I don't completely understand.

Kirsten Yu 2K

Hi, Vy! You were correct about "0.023" only having two sig figs (2 and 3). Because the zeros are leading, they are not significant, as they do not add information regarding the precision of the number.

Kirsten Yu 2K

Thank you so much. Really helpful!

Kirsten Yu 2K

I think the easiest thing to do is just search up your username.

Kirsten Yu 2K

I would focus on the practice textbook problems that are stated in the course outline. Quizlet and flashcards are great for additional help as well!

Kirsten Yu 2K

The limiting reactant in a chemical reaction is the reactant that is totally consumed when the chemical reaction is completed, so yes, it always has the least amount of moles. The amount of product formed is limited by this reactant, since the reaction cannot continue without it.

Kirsten Yu 2K

The reason we use kg instead of g is because kg is the SI unit for mass.

Kirsten Yu 2K

Did you know that you can cool yourself to -273˚C and still be 0k?

Kirsten Yu 2K

I find The Organic Chemistry Tutor, Crash Course, and Khan Academy to be the most helpful!

Kirsten Yu 2K

I love watching The Office, New Girl, The Good Place, and Grey's. Highly recommend if you haven't watched any of them yet!

Kirsten Yu 2K

Personally, I like reading the textbook after lectures. Most of the time, it answers most, if not all, of the questions I come up with.

Kirsten Yu 2K

Thank you so much for sharing! I thoroughly enjoyed reading about your experience and the insights you’ve gained so far on your journey through med school. Wishing you luck on all of your future endeavors!

Kirsten Yu 2K

I totally get where you're coming from. As someone who hasn't taken a chemistry course since Chem H sophomore year, I definitely feel rusty as well. The most helpful thing for me so far has been utilizing Professor Lavelle's modules. They've been really helpful with jogging my memory.

Kirsten Yu 2K

"What would you call a clown in jail? Silicon"

Kirsten Yu 2K

"Did you know that oxygen went for a second date with potassium?"
"How did it go?"
"It went OK2!"

Kirsten Yu 2K

Like some others on this thread, I bought my e-textbook as a rental on Amazon. I like this option because it's so easily accessible.

Kirsten Yu 2K

Personally, I spend the week prior to the final studying fairly heavily until the night before the exam. By that point, there are two possible scenarios. Either I have the material down, and there's no need to study further, or I don't, and there's no point in trying to cram the night before. I usua...

Kirsten Yu 2K

I find it fascinating how prevalent chemistry is in baking. I never put much thought into it until quarantine happened, and my friend and I picked up baking as a hobby. We started by baking cakes, something I now realize is actually an endothermic chemical reaction. This is because heat helps the ba...

Kirsten Yu 2K

Personally, I wait until I've solved the problem before rounding to the appropriate number of significant figures. I prefer to do my work this way because I don't have to worry about rounding too much and throwing off my final answer.

Search found 82 matches