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  1. Dreamerish*~

    Question from surfing acidic environment

    HCl + NaOH → NaCl + H2O nHCl = 0.05 x 0.1 = 0.005 nNaOH = 0.02 x 0.05 = 0.001 .: HCl is in excess. For each mole of HCl, one mole of NaOH reacts with it. We have 0.005 moles of HCl but only 0.001 moles of NaOH. Hence 0.001 moles of HCl will react with the NaOH, and the other 0.004 moles will...
  2. Dreamerish*~

    ionic equations

    Neutral species SrCO3(s) + 2HCl(aq) → SrCl2(aq) + H2O(l) + CO2(g) Ionic SrCO3(s) + 2H+(aq) → Sr2+(aq) + H2O(l) + CO2(g) Spectator ions are those that don't change state. In this case, just Cl.
  3. Dreamerish*~

    Just want to confirm something about tiration

    You fill the burette with a solution, the concentration of which you do know. Whether this is acid or base depends on whether it's the concentration of the acid you know, or whether it's the concentration of the base you know. It's not always base in the burette. In the RACI Titration...
  4. Dreamerish*~

    What U like about ur uni

    I go to USyd, partly because of its prestige, and partly because it was the only university which offered Pharmacy and was at the same time reasonably close to my house. I've only been there for one week, and I suppose it's quite easy to navigate, and the food isn't overpriced. I can't really...
  5. Dreamerish*~

    Heat of reaction calculations

    NaOH + HCl → NaCl + H2O nNaOH = 0.025 x (5.00 x 10-3) = 0.000125 nHCl = 0.05 x (6.00 x 10-3) = 0.0003 .: NaOH is in excess, and that in this reaction, 0.000125 moles of NaOH will react with 0.00125 moles of HCl. ΔH = MCΔT ΔH = 75 x 4.2 x 0.9 = 283.5 J So 283.5 J was released from...
  6. Dreamerish*~

    Electron Orbital Stuff

    Ohh, I get it now! That's not so bad. My lecturer made them sound so hard. Thanks a lot for your help! You too, Riviet. :)
  7. Dreamerish*~

    Decarbonation of soft drink

    Are you talking about a buffering solution in lakes? I wouldn't say lakes are "acidified" - some of them have a buffering system which consists of comparable amounts of a weak acid and its conjugate base - in this case, H2CO3 and HCO3-. The equation is: H2CO3 + H2O H3O+ + HCO3- When acid is...
  8. Dreamerish*~

    Electron Orbital Stuff

    Can anyone explain to me how the electron orbital configuration stuff works? The 2p2 1s3 ... etc? (I just made that up) I thought I'd ask the student I'm tutoring today ... but it doesn't seem fair for him to pay me for teaching me. My school never taught us, and I thought I'd never need it. I...
  9. Dreamerish*~

    What would you like to see on BOS 2006?

    That doesn't deserve it's own forum ... !
  10. Dreamerish*~

    answers to the 2005 paper

    There aren't any answers yet. Board of Studies provided the Marker's Notes but they only give answers to the multiple choice questions. The rest are comments. You might find the marking criteria helpful though. Anyway, you could always post up the question and your answer, and I'm sure I...
  11. Dreamerish*~

    URGENT ONE current use of ethanol

    10-20% of ethanol can be used in modern cars without the need for engine modification. It is hence used as a petrol extender. Ethanol was also used in this way during WWII. I'm pretty sure that this dot point refers to ethanol as a fuel, but other non-fuel-related current uses include...
  12. Dreamerish*~

    a dot point help here!

    They will act as acids when in solution. For example, CO2 is an acidic oxide and it dissolves in water via the following equation: CO2(g) + H2O(l) → H2CO3(aq) The H2CO3 then reacts with water to donate a proton (note that acids are defined as proton-donors): H2CO3(aq) + H2O(l) → H3O+(aq) +...
  13. Dreamerish*~

    just some titration problems

    Do you mean 500 mL? 2NaHCO3(aq) + H2SO4(aq) → 2H2O(l) + Na2SO4(aq) + 2CO2(g) n = m/M .: nNaHCO3 = 11.732/84 = 0.13967 Concentration = 0.13967/0.5 = 0.2793 M 1 being NaHCO3 and 2 being H2SO4: C1V1/C2V2 = 2/1 = 2 (0.2793 x 0.022)/(C2 x 0.0228) = 2 C2 = 0.135 (3 d.p.) Normally I'd do...
  14. Dreamerish*~

    Equilibrium

    Lol well it always depends on the reaction doesn't it? If you want it put generally, the equilibrium will shift to whichever side that will minimise or adjust to the change.
  15. Dreamerish*~

    ENG/ECO/HIST TUTOR - UAI: 99.5 - study full of laughter :)

    Next time I see him I'll kick him in the ass for you.
  16. Dreamerish*~

    which natural indicators did u use??

    We didn't do three. Half of our class did hibiscus flowers while the other half did red cabbage indicator. We cut the red cabbage into thin strips and placed them in a large beaker. Then we filled the beaker with water and brought the water and cabbage mixture to boil. Once the water had become...
  17. Dreamerish*~

    Equilibrium

    1. Which equilibrium are we talking about? 2. What did you do to disturb the equilibrium (increasing pressure, decreasing temperature, adding acid... etc)?
  18. Dreamerish*~

    hair

    Yeah, people with short hair always looked at me going "I want your hair!!!" but it got boring for me after awhile. I've had waist-length hair for like 3 years and it has always been straight because I couldn't be bothered curling. If you can bear parting with your long hair then you can try...
  19. Dreamerish*~

    Hurlstone Agricultural Selective Highschool

    Lol, so studying uglyfies you?
  20. Dreamerish*~

    hair

    My hair used to be up to my waist, but I got sick of taking care of it. Now I have very layered hair that's a bit longer than shoulder-length, and it flicks out a bit. I also have a fringe which covers my whole forehead, but it's one that sweeps to the side. The colour is a deep coppery brown...
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