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  1. Aerlinn

    Equilibrium...

    During the Contact process for sulfuric acid manufacture, sulfur dioxide is converted to sulfur trioxide at temperatures of 400-500C: 2SO2(g) + O2 <---> 2SO3(g); dH= -197kJ mol -In practice, increasing pressure (on this reaction) is usually performed at atmospheric pressures. Suggest why...
  2. Aerlinn

    moles qn

    You have 10g NaCl put into 200ml, which is equivalent to 0.171mol. If that's the amount of mole of solute you have in 200ml, in 50ml you must have 0.171/4= 0.04275mol. You're adding this 50ml to 250ml water, so you're concentration for solution B would be 0.04275/ 0.3=0.143mol/l :)
  3. Aerlinn

    Equilibrium...

    Quick question. The equilibirium constant for the reaction given by the equation: 2HI(g) <---> H2(g) + I2(g) is 48.8 at 455C. An equilibrium mixture in a 2.0L vessel at this temperature contains 0.200mol of H2 and 0.100mol of I2 a. Calculate the concentration of HI in this mixture Hmm... is...
  4. Aerlinn

    A petrol problem

    This is the passage that comes with the questions: During the 1970s, soaring prices for imported petroleum had a marked effect on the New Zealand economy. New Zealand has limited oil reserves but it has abundant supplies of natural gas, which can be readly converted into methanol. A synthetic...
  5. Aerlinn

    Rates

    1a. I dunno, why would those gases concentrate if there's a gas leak? *puzzled* b. Heh, there is no b, I guess c should be b xD c. Aha, so in 'smaller terms' would that mean the lightning's high voltage makes the reaction get over the activation energy barrier quickly? 2b. I suppose... What...
  6. Aerlinn

    Weak Acid Strong Acid??

    I've never heard that. You mean, as in, HBr, HI, HAt (no idea about that last one >.<) are all strong acids too? PS. Speaking of acids/bases, it's strong acids that ionise completely... is it strong bases that dissociate completely into ions, or is that just a misconception?
  7. Aerlinn

    Rates

    Just a few questions: 1. Explain the following observations in terms of the behaviour of particles: a. There have been many explosions in coal mines. (is this because there is more pressure because of a confined space, so your reactions proceed faster because they collide often?) c. Bushfires...
  8. Aerlinn

    Problems

    For that first one, *wacks self over head* You can tell I wasn't thinking properly can't you? I was stupid enough to leave out the actual question, that's why (I give you permission to wack me ^^) Anyway, the WHOLE question this time. Unsaturated oils contain one or more double cabon to carbon...
  9. Aerlinn

    Problems

    Ah, ok... 3)Ok, this is the background to the question, the stuff that goes before it (didnt realise it was needed, sowwi) Unsaturated oils contain one or more double cabon to carbon bonds. Iodine reacts readily with these double bonds: Chemists measure the degree of unsaturation by...
  10. Aerlinn

    chem question - answer them if u think ur smart;

    I seem to have gotten 0.326 mol of O atoms in Q2. Mehbe we're all interpreting it differently :/
  11. Aerlinn

    Problems

    Hm, is this statement, 'a sodium carbonate solution with a concentration of 0.02500M is a primary standard' true/false? I know it's true, but I first had the impression that the primary standard's your pure substance that you dissolve to make the standard solution, not the standard solution...
  12. Aerlinn

    Some questions...

    e. Ek *wacks self* It was burnt in oxygen. I can be a little dumb sometimes.
  13. Aerlinn

    Some questions...

    a. A good result, and only able to do a small amount how? Heh, I'm terrible with my stuff on these instrument analysis things. I figured that HPLC was a type of column chromatography... are there any differences/ major differences? b. Maybe... c. She would probably have a hissy fit if I told...
  14. Aerlinn

    Some questions...

    1. What are the advantages of high performance liquid chormatography for the analysis of durgs compared to an analysis technique based on column chromatography? Hmm... 2. In gas liquid chromatography, why is the column packed with very fine particles? 3. AAS: A solution of distilled water can...
  15. Aerlinn

    Titration things...

    Wonder why the CH3COO- ions don't? Anyways, thanks for everyone's insight. Although I thought that because KOH was a strong base, if it went in the burette, it would be fine because it wouldnt need that much to neutralise the acid? Wouldn't it be the other way around, ie. putting the CH3COOH...
  16. Aerlinn

    ~Trigonometry~

    What's d^2y/dx^2 ? Is that meant to be the symbol for the second derivative?
  17. Aerlinn

    ~Trigonometry~

    I did, nothing loads... Hmm, now it does. Maybe it was my computer :D
  18. Aerlinn

    ~Trigonometry~

    Alright, thanks :) How do I download it? *puzzled* Clicking on the link brings me to a page, which apparently processes a download, but the pdf file doesn't load.
  19. Aerlinn

    Odd thing about dilations...

    I think I get ya. You're saying we shouldn't compare y=(3x+1)^2 and y=(x+1)^2 because they're translated different amounts anyway? Yes I'd been wondering for a while why, when you pop in a dilation factor of 1/3 (the 3), it suddenly gets translated not 1 unit but 1/3.
  20. Aerlinn

    ~Trigonometry~

    I'm stuck on several trig questions: Let x= -2sin(2PIt) + cos(4PIt) +5 be in metres and t in minutes. Use calculus to find the rate of change of x with respect to time t, and find the value of this rate of change when t=4 with an answer correct to one decimal place. Find the first minimum...
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