CHEMISTRY COMMUNITY

Ryan_Kien_1L

Yeah, you can access chemistry community whenever.

Ryan_Kien_1L

I think that a bomb calorimeter represents the closest thing to a perfect system.

Ryan_Kien_1L

I definitely plan on dorming the chance I get, because I really want to try the food everyone keeps talking about.

Ryan_Kien_1L

I was gonna take 14C, but it got filled up too fast so I guess its a break from chem for me.

Ryan_Kien_1L

I make sure to leave time in my day for hobbies, so I at least have something to look forward to at the end of the day.

Ryan_Kien_1L

From what I hear ochem is pretty different from chemistry. I hear just because you're good at chemistry doesn't mean you'll be good at ochem.

Ryan_Kien_1L

I'm looking forward to meeting new people!

Ryan_Kien_1L

Honestly, it's really hard. For me, I make sure to leave a little bit of time to myself every day to keep myself motivated.

Ryan_Kien_1L

Rewatch lectures, attend extra sessions, and the textbook problems are my recommendations.

Ryan_Kien_1L

Based on last semester, I don't think there'll be a study guide, but there will always be those outlines that you can study off of like a study guide.

Ryan_Kien_1L

I kept getting the line diagram wrong because I had coefficients on the right-hand side when there weren't supposed to be any.

Ryan_Kien_1L

In acidic solutions, there are free-floating H+, so you can use that in the equation. If it's basic, there's free-floating OH- so you can use that in the equation.

Ryan_Kien_1L

One of my favorite books is Freakonomics. It's hard to explain what the book is about, but it really changed my perspective on economics as a whole.

Ryan_Kien_1L

Yes, the max number is 50 points.

Ryan_Kien_1L

It really depends on the type of question you're being given. For instance, if they gave you all the other values, you could easily solve for n.

Ryan_Kien_1L

I think attack on titan is a really good watch this season and is worth catching up on if you're not yet.

Ryan_Kien_1L

I'm confident they'll be out by the coming Friday based on past turnaround times.

Ryan_Kien_1L

I think 14BL is a good class to be taking online since Casey is very kind when it comes to grading.

Ryan_Kien_1L

Yeah, from my experience there's no guarantee you'll know until really close to the actual start of the session.

Ryan_Kien_1L

The final consists of everything from week 1 - 10.

Ryan_Kien_1L

I mostly just end up playing games or sleeping the day away.

Ryan_Kien_1L

I highly recommend Dr. Casey, she provides a wealth of resources to help you succeed, including extra credit.

Ryan_Kien_1L

Yeah, it's really hard for me to stay on top of things when there seems to be a midterm every week. I try to pace myself, beforehand to not run into these issues, but when they arise, I try to get to a place where I have no option but to work.

Ryan_Kien_1L

For me, I try my best to pace myself with small breaks in between.

Ryan_Kien_1L

I'm going to chill a bit next quarter and finish my language requirement, math 31b, and a GE probably

Ryan_Kien_1L

Deadlines are always Sunday at midnight, but I've heard of some leeway from time to time.

Ryan_Kien_1L

You pick the R that has matching units that cancel out all the other units in the equation.

Ryan_Kien_1L

Yes, you figure out the molecular shape through VSEPR.

Ryan_Kien_1L

Yes, by definition, I believe positive delta H is endothermic because it's a gain in energy, meaning a positive delta H.

Ryan_Kien_1L

I always make sure I'm caught up on lectures and hw early. Spaced repetition is really helpful when it comes to memorizing concepts.

Ryan_Kien_1L

To my understanding, Delta U is = 0, when the volume is constant.

Ryan_Kien_1L

Essentially, there's a lot more energy in steam than water because it takes a lot of energy for water to become steam. For that reason, steam transfers a lot more energy than water.

Ryan_Kien_1L

I'm planning to take 14C next semester because I'm trying to get as much done during online classes, while I have the time. However, I think both options are fine because I hear 14C, is quite different from 14A and 14B.

Ryan_Kien_1L

He's pretty quick when it comes to grading the midterm. I wouldn't be surprised if we got it back by the coming Friday.

Ryan_Kien_1L

arisawaters2D wrote:Thank you! So just to clarify the second deprotonation will always have a smaller K value than the first?

Yes, and the third Ka, if there is one, will be smaller than the second as well, because they become less acidic.

Ryan_Kien_1L

I'm taking 14BL right now, and it seems perfectly manageable with Chem14B.

Ryan_Kien_1L

-log of H+ concentrations yields pH. -log of OH- concentration yields OH-.

Ryan_Kien_1L

For me, I felt like the first and second midterm were definitely much more than enough time. I do feel like the timing was more difficult as the quarter went on though.

Ryan_Kien_1L

A phase change is simply when an object changes from one state to another. It does not necessarily have to be between a solid and a liquid.

Ryan_Kien_1L

Temperature can be seen as a measure of kinetic energy. Cold packs are endothermic because the pack is taking energy from the outside, and storing it within itself, making the area around it feel cold, due to the lesser energy.

Ryan_Kien_1L

One arrow means that a single direction in strongly favored.

Ryan_Kien_1L

In 14A, my TA said that any calculator was fine and didn't bother checking any of our calculators before the exam.

Ryan_Kien_1L

I wouldn't stress out about how Sapling looks in the grade book because it's based on completion as long as you have it done before the deadline.

Ryan_Kien_1L

I've definitely heard about some leniency about chemistry community posts, so just try your best to catch up, and there's a good chance you'll be bumped up, regardless.

Ryan_Kien_1L

I was told that the midterm this quarter would be pretty much the same format as last semester, except in lecture period

Ryan_Kien_1L

I think that the most important study strategy for this class is simply utilizing the textbook questions. A lot of them are similar to the questions that would appear on the exam, so if you easily understand the textbook problems, then you can be confident on the exam.

Ryan_Kien_1L

I believe that a very large K would mean what you said because it would assume that there would be no desire to have very much reactants at equilibrium.

Ryan_Kien_1L

The equilibrium would shift in a direction based on whether the reaction was endothermic or exothermic.

Ryan_Kien_1L

Favors products -> The reaction wants to have a greater concentration of products
Favors reactants -> The reaction wants to have a greater concentration of reactants

Ryan_Kien_1L

Based on the last final exam, I'm pretty confident that going over all the textbook problems again would be really helpful to make sure that you still remember how to apply concepts, and they show up on the exams sometimes.

Ryan_Kien_1L

From chem community in 2018: "Exothermic/Endothermic: refer to transfer of heat or changes in enthalpy
Exergonic/Endergonic: refer to changes in free energy"

viewtopic.php?t=26526

Ryan_Kien_1L

darchen3G wrote:Yes there will be hydrogen bonding, dipole-induced-dipole, and London dispersion forces.

I don't think there will be hydrogen bonding CO2 and H2O because the oxygen in CO2, isn't connected to Nitrogen, Oxygen, or Flourine.

Ryan_Kien_1L

Lone paired electrons take up more space than the usual bonds, which could result in a slightly smaller or larger bond angle.

Ryan_Kien_1L

I've had the same thing before. The best thing you can really do is try to get on a different wifi network, device, or just wait for a later time if none of those work.

Ryan_Kien_1L

The two make carbonic acid, which makes the solution acidic.

Ryan_Kien_1L

I'm pretty confident we need to memorize all the shapes.

Ryan_Kien_1L

Yes, the same applies for strong acids/bases as well.

Ryan_Kien_1L

Something I definitely plan on doing is attending Lavelle's Chem Review on Wednesday and Friday since he'll be going over last year's exam there.

Ryan_Kien_1L

I personally think that it depends on your definition of acids and bases (ie. Bronsted-Lowry, Lewis, Arrhenius). So the first thing you'd need to do is identify which definition you're looking for.

Ryan_Kien_1L

Strong Acids tend to be one's with 7 valence electrons with some exceptions and strong bases tend to be ones in the 1st and 2nd row with few exceptions. The best way is just to memorize them since there's only a few.

Ryan_Kien_1L

It's loading fine for me now. I heard CCLE was down earlier today, so that might've been it.

Ryan_Kien_1L

I don't necessarily have any tips for memorizing the molecular geometry aside from try drawing out the shape. I thought this graph was pretty helpful for understanding how multiple shapes could be considered T-shaped, or Bent. https://sites.google.com/a/coe.edu/principles-of-structural-chemistry/_/r...

Ryan_Kien_1L

I began to realize how important workbook problems are because they actually show up on the test. I definitely take the time to memorize the answers to questions I don't necessarily understand.

Ryan_Kien_1L

I assume that they leave it vague intentionally to leave room for curving later on.

Ryan_Kien_1L

The angles immediately near the electron would increase, while angles further away would increase because the electron pair creates more space for itself.

Ryan_Kien_1L

From my knowledge, 6 electron regions with one electron pair are square-pyramidal and a trigonal bipyramidal would be 5 electron regions total.

Ryan_Kien_1L

12 units are the minimum, so I wouldn't stress about it too much!

Ryan_Kien_1L

XeF2, could be seen as linear because the lone pairs of electrons would be equally evenly dispersed between the outer atoms, thus making them still form a line if that helps you visualize it.

Ryan_Kien_1L

I try to force myself to walk my dogs every morning when I'm up early enough.

Ryan_Kien_1L

You would determine it based on the shape of a molecule. For instance, this shape is octahedral, meaning the bond angles are ~90 degrees, I think.

Ryan_Kien_1L

I think of step-up as sessions you go to if you think you struggle to understand the content and want to go through it "step-by-step". Drop-in would be kind of like office hours with a TA, where you ask specific questions you want answered.

Ryan_Kien_1L

The way I thought of it was that all molecules have a dipole moment, as they all display London Dispersion Forces.

Ryan_Kien_1L

I think the most important things are the saplings, rewatching the lectures, and doing the assigned textbook problems. If that's not enough some TA's have review sessions that highly recommend.

Ryan_Kien_1L

click on your name and it should tell you how many posts you have. Just remember each week requires 5 posts so remember to account for that when calculating if you get all your participation points. If we didn't do a full 5 one week, but then made up for it the next week does that count? Like only ...

Ryan_Kien_1L

Nitrite and nitrate are two different ions based on the number of O-. I'm not entirely sure if we're required to know the structure for both of them, but I definitely think it helps to put in the effort to differentiate the two because they came up a lot during my time in HS.

Ryan_Kien_1L

Lewis acids are molecules/atoms that accept electron pairs. Lewis bases are molecules/atoms that "give away" their electron pair.

Ryan_Kien_1L

If you look at solubility rules, silver is typically in exception in most cases.

Ryan_Kien_1L

London dispersion forces (aka Van Der Waal Forces) are the weakest force between molecules that happen when molecules become temporarily polarized as electrons move around.

Ryan_Kien_1L

I'm honestly pretty happy with the way things are right now. I feel like I'm getting the hang of things, but my free time has definitely gone on a decline.

Ryan_Kien_1L

Yeah I'm pretty sure it's gonna be the same format

Ryan_Kien_1L

It's Hz/Hertz, however, Joules is the unit for energy, not hertz. Hertz is the measure of frequency.

Ryan_Kien_1L

I like to convert things into SI units as soon as possible, so I don't forget later.

Ryan_Kien_1L

I don't have anything to work with at the moment but make sure you convert the nanometers to meters because that tripped me up the first few times.

Ryan_Kien_1L

I remember my TA telling me that the reason we don't get our grades back right away is specifically for issues like that, so I wouldn't worry about it.

Ryan_Kien_1L

Atomic radius is largest at the bottom left of the periodic table and weakest at the top left. You can assume that the atom gets bigger when it gains shells which could explain the phenomenon when it moves from top to bottom. The way I was explained the phenomenon from left to right in AP chem was t...

Ryan_Kien_1L

The total uncertainty is the range of numbers that the answer could be, which is why you multiply it by 2.

Ryan_Kien_1L

Review sessions happen every week. The schedule is posted here: https://lavelle.chem.ucla.edu/wp-conten ... PL_ALL.pdf

Ryan_Kien_1L

Here are some review sessions held every week I belive: https://lavelle.chem.ucla.edu/wp-conten ... PL_ALL.pdf

Ryan_Kien_1L

I think the best way to study is to do the textbook questions and make sure you understand everything he says in the lectures. Rewatch them if you need to.

Ryan_Kien_1L

Dr. Lavelle recently sent out an email about most of the midterm logistics if you have any more questions.

Ryan_Kien_1L

You don't need to memorize any formulas. I think I was told the main focus of our studies should be to learn how to apply and manipulate them.

Ryan_Kien_1L

At least for my TA, he wanted us to buy a seperate USB webcam, so he could have a sideview of our desk the entire time.

Ryan_Kien_1L

I believe I heard that someone's TA said that it would be multiple choice

Ryan_Kien_1L

I got my Sapling Access card maybe a week after I ordered mine for shipping, I would shoot them an email if you're getting worried, but I assume you should be able to just walk in and get it.

Ryan_Kien_1L

I know for my TA, they requested we have a USB webcam, because they wanted to be able to see our desk the entire time.

Ryan_Kien_1L

Yeah, I think he said in the first lecture that the main focus of the exams was to see our ability to apply the equations not to memorize them, so we'd get an equation sheet.

Ryan_Kien_1L

You would always round your final answer to the lowest number of significant figures from the constants you're working with. If the only constant you're working with is an element off of the periodic table then your result would be 4 significant figures.

Ryan_Kien_1L

If you do stochiometry, you can generally figure out what the final units are by crossing out units if the units on the numerator side match the units on the denominator side. The remaining unit at the end should be the units in your answer.

Ryan_Kien_1L

Oxygen gas is O2 in this case. When elements are in their natural state some of them appear in doubles. You know its a double in this case because you're told its oxygen gas.These elements that naturally appear as doubles are labelled as diatomic molecules. I think they're hydrogen, nitrogen, oxygen...

Ryan_Kien_1L

The moles of each individual element must remain constant for both sides of the reaction, the total number of moles of molecules can change.

Search found 102 matches