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  1. Aerlinn

    Multiple choice

    A worksheet from our teacher ^^ You mean, ending up with 2x= x (which should probably be some other letter since they're not the same number)? To me that says... twice the mass of oxygen as there is SO2...? >.<
  2. Aerlinn

    Multiple choice

    The answer says B, i know that much (of course, it could be wrong...) I tend to 'sort of' agree with TesseracT22... It a gas has more moles, it probably should exert more pressure. Though i'm not sure i understand how it can be deduced that from no. moles of O2 is x/32 and no. moles SO2= x/64...
  3. Aerlinn

    Multiple choice

    If no. moles of O2 is x/32 and no. moles SO2= x/64, doesn't that say that SO2 has half as many moles? *ponders* I am slightly puzzled =S
  4. Aerlinn

    Multiple choice

    The first one, thanks :)... I thought that that's what i did, but maybe I didn't do the calculations properly somewhere The second one... hm, that would give D as the answer, but the answer's B... =S ~~~ Update: This question... Ammonia reacts with oxygen to form nitrogen dioxide, NO2...
  5. Aerlinn

    Multiple choice

    Two questions which I figured out I couldn't figure out how to do (they dont look hard, though :bomb: ) A sample of 1.00g of a pesticide is analysed for its arsenci content by precipitation of the arsenic as the sulfide, As2S3. If 0.123g of the sulfide is obtained, the percentage by mass of...
  6. Aerlinn

    Urgent: Couple of questions

    1) Hmm, for some reason, that doesn't strike me as logical, 'cause... I don't understand :'( *sniffs* 2) In some places they have states as liquid, in others, aqueous. I guess it probably varies with what you've got? 3) Interesting... what are these 'complicated reasons'? ^_^
  7. Aerlinn

    Urgent: Couple of questions

    Okay, thanks :)
  8. Aerlinn

    Urgent: Couple of questions

    Some quick urgent questions: Oxidising CH3CH2OH to CH3COOH... Cr2O7(2-)/MnO4- (these are meant to be above the arrow) CH3CH2OH(aq) ----> CH3COOH(aq) H+(aq) Why does the oxidant, eg. acidified potassium dichromate, have to be...
  9. Aerlinn

    Sulfuric Acid

    I see... ~~~ Something I wanted to clarify: you get sulfur/ sulfur dioxide from incomplete combustion of H2S in natural gas/ crude oil... 3H2S(g) + O2(g) ---> 2H2S(g) + 3S(g) + SO2(g) Is that done as part of the desulfurisation process? ie. removing sulfur-containing...
  10. Aerlinn

    Industrial production questions

    Heheh, okies. Thanx for that :) And other oddities... 1. Give examples from an industrial process to show the significance of the following factors in chemical industry: -concern for the environment (I can only think of reducing SO2 emissions when manufacturing H2SO4...) -energy costs...
  11. Aerlinn

    Condensation

    Where there's a condensation reaction you have two reactions put together, say two monomers, eg. an alcohol and a carboxylic acid, and a small molecule eg. water is removed and comes out as a product. The reactants join up.
  12. Aerlinn

    Ethene to Polyethene

    Dont know about what catalysts, but they're probably used simply to speed (like all catalysts) up the polymerisation...
  13. Aerlinn

    Industrial production questions

    Some evil questions I came across: 1 Explain why ethane, the feedstock used in the thermal cracking process, is present among the products and suggest what would be done with this substance. 2 What are the main reasons why the clustering of companies in the Altona Complex is commercially...
  14. Aerlinn

    Help! Simple Mole calculation...

    Yeah, what you're doing is right. The mass is in grams. Though when it asks 'determine the amount', I'd usually interpret it as 'find the number of mole'.
  15. Aerlinn

    Urgent: Interpreting experiment

    1) yay ^^ Hm, counter ions, what do they do? (keep solutions neutral?) Are those kinda like spectator ions? So would the NaCl affect the [Cl-] too? My teacher was all 'normally you should avoid using ions which are present in the equilibrium expression. Huh? If that should be avoided, wonder...
  16. Aerlinn

    Sulfuric Acid

    Thanx :) Ah yes, i remember being told that, I think. So we'd find [H+] in the second ionisation by treating HSO4- as a weak acid then add the [H+]'s together? (I also remember that before we did this stuff, we used to calculate pH's by going, eg. for this one, [H+]= 2* 0,050M Now why on...
  17. Aerlinn

    Urgent: Equilibrium bits and pieces

    Yes, that's true. Just wondering whether it's 'more' important to mention K, or equilbrium position that's all Heheh, ooops, SO3 should increase, you're right :)
  18. Aerlinn

    Urgent: Interpreting experiment

    well, that's what the experiment sheet said, so, it's according to my teacher =S I don't know about the latter, but Co2+, I think CoCl2 is blue, but CoCl2 6H20 (the hydrated crystals) are magenta/pink, so CoCl2 6H20 might be what it's talking about?
  19. Aerlinn

    Urgent: Interpreting experiment

    We did an experiment with the equliibrium: Co2+(aq) + 4Cl-(aq) <---> CoCl4(2-) (aq) Co2+(aq) is pink (I'm guessing it's hydrated crystals in solution, 'cause anhydrous CoCl2 is blue?), Cl-(aq) is colourless, CoCl4(2-)(aq) is blue. Basically, we did 3 tests. Test A: Temperature change. Test...
  20. Aerlinn

    Urgent: Equilibrium bits and pieces

    equilibrium displacement?
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