Chemistry
For Chemistry Discussions
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We are suppose to write design about it. I have problem to formulate two contrasting methods. It is required to write Lab design and suggests two contrasting methods (that is ones that are based on different physical/chemical principles and hence have different inherent errors in them) to measure the solubility at a specified temperature and write a brief outline of both methods. It's my first time suppose to write a chemistry lab design, can anyone help?
Last reply by Keel, -
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How does this work? Which/How is a buffer produced in this reaction? I assume CO2 gas can be measured to determine the rate of reaction for each pH solution?
Last reply by Drake Glau, -
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hey, I am doing an investigation on the effect of capillary tube forces on different length of capillary tubes. The dependent variable is the height of the liquid (water) in each tube. What do i need to know for this investigation and has there to be any calculations. I am so lost:( please help !
Last reply by littlemouse, -
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After a very long, convoluted series of events, I ended up making a looot of reeaally concentrated KMnO4. I have way more KMnO4 than I'll need for the two labs I was going to use it for. Do you guys have any idea for yet another lab I could use the rest of the solution for? I'm not expecting you to give me the entire procedure or tell me anything in too much detail, but I just seriously have way too much solution and I really don't want to waste it (lest face the wrath of my chem teacher) and am just looking for any ideas in general. It doesn't even have to be a good design - I'm also currently trying to think of some total crappy fail lab to do so I can do a really detai…
Last reply by wombat123, -
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Whats the diff between a combustion reaction and just heating a substance? Also, in a combustion reaction, are the products always carbon dioxide and water, or is it a common oxide of the reactant and water?
Last reply by dessskris, -
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Hi, Could someone knowledgeable in chemistry IA's check over my 'design' and give me some feedback? Thanks
Last reply by ILM, -
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In Biology and Chemistry, when I'm looking for definitions or simple explanations, sometimes I look up to text book, encyclopedia, and so on. I'm wondering, can I directly refer it as my reference? Or should I write other sources, and use other sources?
Last reply by timmotytimmoty, -
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My teacher is making our class do the analytical chem option, and I'm having a lot of trouble figuring out IR, HNMR, and mass spectrum graphs. Do you guys know any good links, sites, books, etc. that have good explanations regarding those?
Last reply by dessskris, -
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So, I've been working on my essay, and I've chosen to do an experiment of pH level of wine as it ferments. Well, there's one problem there: I have no idea how to properly do a titration measurment of pH. I'm doing the equallibrium and acid-base chemistry sections by myself (I'm in year 1, we don't do it until year two), and I'm slightly overwhelmed by everything that I have to learn. Could someone please explain titrations to me in lameman's terms, so I can get a good idea (considering I have to know how to do them by Saturday, I'm kinda stressing. :0 Thank goodness for PD days) Any help is muchly appricated!
Last reply by URA BOAT, -
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Hi guys, just wondering, I'm doing this same IA and I have to show that water is the excess reagent by showing that the number of moles of water is higher than the no. of moles of Copper sulphate. How do i do this if i cannot calculate the Mr of H2O because there is no coefficient? So basically I want to show how it is limited
Last reply by Sleeping Beauty, -
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Hi guys, just wondering, I'm doing this same IA and I have to show that water is the excess reagent by showing that the number of moles of water is higher than the no. of moles of Copper sulphate. How do i do this if i cannot calculate the Mr of H2O because there is no coefficient?
Last reply by Keel, -
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This is the reaction I am indirectly finding CuSO4 + 5H2O --> CuSO4.5H2O These are the two equations I am using to construct the Hess' cycle 1. CuSO4 + xH2O --> CuSO4(aq) 2. CuSO4.5H2O + xH2O --> CuSO4(aq) What should the coefficient of H2O be?
Last reply by JHYC, -
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I have a tiny question. Does a high percentage uncertainty mean low precision? Or does it have nothing to do with it? Thanks for your help guys, lab reports totally screwing with my mind :/
Last reply by timtamboy63, -
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I have a quick question about SL Chemistry that I hope someone can help me with. I'm not too sure about my future career choices, so I'm trying to keep my options open at the moment. I'm wondering if a SL chemistry credit will be enough to get me into life science programs in universities in North America, if I decide to go into medicine? About 85% of my grade are taking HL Chemistry, and they're making it seem like it's the worst decision you can make to NOT take it. This is making me incredibly confused and stressed as I have to make the decision sometimes next week. Thanks in advance.
Last reply by URA BOAT, -
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Hi everyone! I'm currently taking SL chemistry but due to timetable issues and subject choices I will need to start to take HL Chem. Currently I'm getting solid 6s, will I be able to maintain this in HL? Tommy I'd also like to access this file to have a look at the content but it simply returns an error.
Last reply by tank85, -
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How could I make aluminum not oxidize in an experiment?.. Is there such a way
Last reply by Mart, -
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I tend to do well in paper 1 but not so well in paper 2. As the final exams are quite soon. I was wondering if anyone had any good ways of studying for paper 2
Last reply by dessskris, -
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Hello I am a IB student who failed to aquire a IB diploma on my 2011 march exam.. I have achived all good grades except HL Chemistry. I am willing to only just pass the Chemistry HL. I know that lab reports are something like 24% of finall grade and I need at least 3 as passing grade (which is combination of lab reports grade and exam final grades). Sooo,what if i get (4, or 5 or 6) on my Lab reports, what exams grade I need to get in order to pass? (pls do the math for me)
Last reply by Rigel, -
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What would happen to the voltage, or the electrical potential of a copper-zinc voltaic cell if the concentration of the electrolyte solution (CuSo4) were to increase?
Last reply by Keel, -
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Hello all. I'm planning a Chem Lab for Acids and Bases where I'm measuring the rate of reaction between HCl and Mg by measuring the rate of effusion of hydrogen gas. However, I'm not sure if it is feasible to measure the rate of effusion of a gas with a gas collection tube. I was wondering if this is in fact a good idea, or if I should change my experiment, because we have no other equipment available to measure the volume of gas given off.
Last reply by Keel, -
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So My boyfriend is failing Chemistry. We have no idea why but he literally has an F. He's such a hard worker so it's not like he's lazy or not doing his work. We're juniors in IB and we have a great teacher. I've helped him study for tests before and... he wants to give up. What do we do??
Last reply by The Filipino Limner, -
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My textbook is really crappy (A nelson gr 11. chem. tb that every single gr.11 chem. student uses in ontario), and my teacher does not neccesarily explain that well in class. Should I search up whatever I'm learning online? Or is there a textbook that I can buy specifically for chem. IB (SL or HL).
Last reply by The Filipino Limner, -
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I recently did my trial exams for chemistry paper 3 and found that a lot of the questions ask stuff like: - state TWO reasons for (...) - state ONE advantage and one disadvantage of (...) so I was wondering if you state more reasons than what they ask for, but one of your reasons are wrong, would you still get the full marks? for eg. if the question was worth 2 marks and I gave 3 reasons, 2 were right and one was wrong, would I still get 2 marks for having 2 correct answers or would I be penalized for having one wrong answer?
Last reply by Keel, -
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Hey! Throughout the course I've been using the mentioned textbooks to study for tests and exams. However, I have encountered a few errors (I made sure they were by checking with my teacher and websites) and thought that we should compile a list to prevent ourselves from learning something that is incorrect or irrelevant. IB Chemistry Course Companion by G. Neuss (blue cover) Structure & Bonding: - Pages 66-67: Resonance hybrids is misplaced as it is HL only; it should be in the HL part of Bonding and structure Energetics: - Page 102: The Born-Haber cycle diagram seems to be missing in some prints. Refer to this: Click me! Option G - Page 373, Figure 4: "The nucleophil…
Last reply by Phillip7000, -
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Hello fellow IB Students Ever since i had started taking the HL course in chemistry, I have managed to sustain a 4 throughout the year. Howwever,with many attempts in vain, i couldn't surpass that grade. I have talked to my teacher about it and he told me that i rely on the theory too much and donot apply my knowledge effectively.I have no idea what she means by that and if I knew so, how would i go about and get on track ?
Last reply by CkyBlue, -
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Someone knows how to do these exercises? 1. Evidence suggests that the reaction between nitrogen dioxide and fluorine in the gaseous state is a two-step process: 2NO2 (g) + F2 (g) --> 2NO2F (g) STEP 1: NO2 (g) + F2 (g) --> NO2F (g) + F(g) (SLOW) STEP 2: F (g) + NO2 (g) --> NO2F (g) (FAST) s) State wich is the rate-determining step, and explain why. b) State wich of the two steps is expected to have the higher activation energy, and explain why. c) Give the rate expression of the reaction based on your answer. d) What feature of the fluorine molecula makes it reasonable to propose that a fluorine atom may be formed as an intermediate in this reacti…
Last reply by Keel, -
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Does freezing point neccesarily mean the temp. when the substance is COMPLETELY frozen/solidified, or when the first few crystals begin to form (aka during midway/beginning of solidfying)...? Cuz I did a lab on naphthalene cooling curve, and I was wondering...
Last reply by Keel, -
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I'm curious why metals have particular colors. How does the metallic bonding affect the emission and how is the spectrum produced from the metallic bonding?
Last reply by Keel, -
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So we got the chance to do a mock lab report whhich our teacher corrected, and she told me that mine was extremely messy.... so I have to correct some things that i know how to do, but i also have to do 2 things that i have no idea about: 1)when i do a table with measurements, should I write the uncertainty next to each mesurement or just on top next to the unit and name of the variable? 2) i wrote my processed data at the bottom of each segment of the experiment, but apparently "it is not presented as required" does anybody have an idea of how are we supposed to "present the processed data"? if you could help me out i would be extremely helpful ))
Last reply by Keel, -
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What/how do I put references after the conclusion in the "References" section? If I used online websites, should I just copy and paste the links? Cuz it says to CITE IN PROPER FORMAT...but idk what the proper format is for a chem. IB Lab..
Last reply by dessskris, -
Lab Report Worried sick about Chem Labs
by Guest KAPOWW!!- 2 replies
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Hey guys, I haven't finished a single lab and I'm in year two and running out of time slowly and steadily... I need help with Lab ideas desperately(Can I do IAs that other people are doing/have done?-no I won't copy anything but the title) So far I've thought of a DC and Design Lab that is, I'm performing a thermometric titration. Can you throw in some Ideas, because I really can't think of any, and when I see all those sample Labs from the IB website I'm astounded, I don't get what they're talking about! Thanks! PS Mods- I hope this doesn't violate any rule, sorry If it does.
Last reply by dessskris, -
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Yesterday, we did our first lab in the chemistry HL IB course (gr 11). I wasn't used to it at all, like having to set up and do nearly everything by ourseleves without assistance. Plus, gathering the data knowing that you cant rewrite your data the next day (because our teacher was going to check it as soon as we finished) made it difficult because I was always used to going home and checking with everyone to see if I got the best data.... I already lost marks for not following one of the safety rules during the lab....------- Can anyone help me with some really good general/specific advices regarding on how to write/organize labs in order to achieve the best mark possib…
Last reply by dessskris, -
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Hi guys, This particularly applies to November 2011 people, but any input would certainly be appreciated! Particularly from those who have been there I was wondering how you are structuring your revision of the syllabus? Are you only going through the topics that you remember struggling with or systematically? How do you work out your areas of weakness? What strategies do you use to know your options inside out? I have my mock exams in about 3 weeks and I'm more than a little bit nervous! I have no idea where to start Thank you!
Last reply by tum_tum_tree, -
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I am going to be a junior this year and am planning on taking HL Biology next year (meaning I have SL Biology this year). This year I have ceramics and Math Studies, which will clear up 2 spots next year, but also means I will need another SL class. I want to be a veterinarian and am considering doing SL chemistry along with HL biology for my other credit, and taking a fun class in place of math so that I can have more "breathing room" to focus on exams/papers/essays etc. What's your thought on that? Is SL chemistry really hard?
Last reply by Sixthrain, -
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hi everyone, im going to be new to IB in about a month and i have taken HL Chemistry. Im worried on how I will cope, can more experienced users tell me how they find this subject, in terms of work, assessments, tests, etc? thanks
Last reply by Lero, -
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I am a rising senior and I am reviewing the topics for IB. I had a question about chapter3 Periodicity (according to my book it is chapter 3 IBID 2007) regarding complex ions. It is stated that it is formed by the unfilled p orbital that the transition metals poccess. But how does the isomers form??? According to my understanding that the ligands are the same... then how come it is possible to have isomers in complex ions? BTW, how is my textbook version? I had another confusion in P88, why the iron presented in the complex ion has a oxidation number of 1 or 2, in the contrary of 2 or 3 as general concensus?? One last question, can lab reports be self-made i.e self-writte…
Last reply by daxx, -
Organic Chemistry doubts!
by Guest KAPOWW!!- 5 replies
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The textbook states water is a weaker nucleophile than OH- because it lacks a negative charge, Doubt 1- How is water a nucleophile in the first place when it has no charge?
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Answers to Organic Chemistry worksheet?
by Guest KAPOWW!!- 18 replies
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Hey this organic chemistry worksheet seems great, except that it has no answers. So could someone help me find the answers, or if you're really good at Organic ;post them yourself? Its attached too! Thanks!! TheCompleteOrganicChemistryWorksheet.pdf
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My first day back in chemistry left me in shock. The teacher that we had last year who had taught HL chem for several years no longer teaches it and we now have a teacher who A) has never taught IB chemistry or even in IB before and B) hasn't even taught before! I'm not saying she's a bad teacher but I have a bad feeling that we're not going to accomplish much this year. Being a person who's aiming for a 6 or 7 in chemistry I think I'm going to end up having to learn a lot of the material on my own. So all you chemistry people who've taken the exam before, what's the best way to go about learning the material? I have the Pearson Baccalaureate HL chemistry book and the Ne…
Last reply by Rigel, -
Enthalpy sums please!
by Guest KAPOWW!!- 0 replies
- 608 views
D-day is on Tuesday, I don't have much time left...may be you could do this for me as my last wish *coughs* Could you post the names of past papers that have sums on enthalpy, in terms of deducing the heat gained in the reaction and all that stuff with Q=mc dt , you know? Or Perhaps if you have some links, I'd be cool with that too. I hope I will be missed...
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Tips on approaching Organic Chemistry
by Guest kenshi64- 6 replies
- 3.1k views
Hey, i'm going to have Organic Chemistry for the first time for my exam so I have no clue as to what I should pay attention to and what not and what weightage-if that word exists, the questions receive and anything else you think would help me nail Organic, Thanks buds! Cheers!
Last reply by Emmi, -
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can anyone help me with my lab report on 'observing emission spectra' my task was to observe the emission spectra from various sources and account for the differences in their appearances. thanks!
Last reply by dessskris, -
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I was going through some past papers, and I got stuck on a question. Which list represents the halogens in increasing order of oxidizing strength (weakest oxidizing agent first)? A. Cl2 I2 Br2 B. I2 Br2 Cl2 C. I2 Cl2 Br2 D. Cl2 Br2 I2 I'm really confused about what this question is asking. It says 'increasing order of oxidising strength' but then 'weakest oxidising agent first'! From what I know, these two contradict each other ,no? what oxidises loses electrons, and what reduces (oxidising agent) gains electrons. So does this question want me to list halogens that are least likely to oxidise -> most likely? or most likely (weak oxidising agent) -> least …
Last reply by Ezeh, -
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hi there, what is the theoretical value of RMM of amidosulphuric acid? thnkz
Last reply by Keel, -
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Well That's why I thought a thought provoking IA, I learned in class of Oxygen's tendency to bond to positive ions, so I though lets put this idea through a test. And please cite a resource for your belief since It can be incorporated into my hypo and so that I can show it to my teacher too, Thanks a million!! Carbonly Group This group is found in Ketones, Aldehydes etc
Last reply by dessskris, -
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Hello everyone, I'm taking IB Chemistry HL, and I have a really terrible teacher. She is way too slow, doesn't explain anything well, and gets corrected by us students on a daily basis. She's so slow that we still haven't finished topic 4, and our first year of IB ends in less than 2 months. So, as you can guess, I'm really freaking out. I've been worried since the first month of school that we wouldn't be able to finish everything on time, but I never thought we'd still be on topic 4 by the end of the year! I've been looking for online resources so I can teach myself this summer, but I haven't really found anything yet. If any of you have any websites, youtube channels, …
Last reply by Lero, -
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does anyone know what the variables are in this prac? and also what to include in the processed data?
Last reply by giraffe26, -
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Hi I just got my IB results and I got a 7 in chem higher level, I was just wondering if anybody knows how many people achieve a 7?
Last reply by puka3300, -
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Hi, I am new to the chemistry sub-forum, so I am sorry if I have done anything wrong in advance. The prac was to prepare the transition metal complex tetrammine copper(II) sulfate. In this prac, we were required to vacuum suction the compound to remove all water so we could attain an accurate mass. However, the flask contained water which was slightly blue. Does this mean there was copper ions in the water or the entire metal complex? Also, I didnt understand the concept of solubility in this prac, why did we have to cool the solution in ice water? And how can I discuss this? Finally, what was the point of using ethanol in the prac? Something to do with polarity but I…
Last reply by Drake Glau, -
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I have to do a Lab Report on the topic of kinetics involving the Activation Energy of a reaction by measuring the rate of a reaction at different temperatures. What I cannot get my head around is how can I find calculate the activation energy (presumably using the Arrhenius equation) without the rate constant and the Arrhenius constant of the reaction? I am quite "confuzzled" (yes, that is the extend of my confusion) and any suggestions whatsoever would be greatly appreciated.
Last reply by Drake Glau,
