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    Comparison of Unis for Science - USYD vs UNSW vs ANU

    I was wondering if anyone had some insight they could give me into a comparison of science courses for USyD, UNSW and ANU - specifically Bachelor of Advanced Science/Advanced Studies (at USYD as a Dayell Scholar), Bachelor of Advanced Science/Computer science (at UNSW) and the Bachelor of...
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    Simple Keq Acid/Base Reaction Question

    Very sorry if this is a pretty stupid question, probably just a pre-exam freakout: In a beaker, 50 mL of 1.0 mol L−1 CH3COOH is reacted with 30 mL of 0.70 mol L−1 NaOH. (Ka of CH3COOH = 1.7 x 10−5) Calculate the pH of the final solution My confusion is how are you supposed to calculate the pH...
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    BoS Chemistry Trial 2021

    Firstly, epic exam to everyone involved in making it - tough multi-choice section, the free-response part required problem-solving, very good paper. I'll hold my questions for now until the solutions are posted (When would that be?), but just quickly - The last question talked about Tollen's...
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    2021 BoS MX2 exam

    Oh so is this going to be like mastermind where we keep guessing? Nah, I'm kidding, but that's pretty interesting that only 1 of the 4 identified was correct. Are the 3 that most answered amongst 1, 2, 3, 4? The only other question I could think of being the "hardest" question was 6
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    2021 BoS MX2 exam

    I agree that 8 seems like the one less than 50% got right, but think the >70% ones are 1,4 and 7 (Though I am not too certain about 7, perhaps it was 2? I would say 3, but not a lot of people are too comfortable with that notation IMO). I did think this was a lovely multi-choice section...
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    Parramatta Marist 2020 - Mex2 Paper

    Actually on the second question, is the method: (Apologies for not using right formatting): - Integration by parts on the middle one, which gets the inequality (As it is greater than 0 by inspection) I_(n-1) < e/n - Using this to show er < n+1 - There will always be an n to fulfill this
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    Parramatta Marist 2020 - Mex2 Paper

    2 Questions: 1) is Q22 a) correct, because I'm under the impression it should be 100j (Instead of j) in the given equation 2) How exactly do you go about showing Q23? I imagine it is insufficient to show the integral approaches 0 as n approaches infinity, therefore there will always exist an n...
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    Dipole-Dipole vs Hydrogen Intermolecular Bonds

    A lot, thank you very much
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    Identifying Esters/Carboxyllic Acid

    What I mean is if the oxidising agent that you add is acidified, then irrespective of whether the aldehyde is oxidised to the ketone, the sodium carbonate will still produce CO2 gas. The same applies for a litmus test
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    Identifying Esters/Carboxyllic Acid

    Also, forgot to put it in OG question, what is the identifying test for alcohols? (Just whether it has formed, not differentiating them)
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    Identifying Esters/Carboxyllic Acid

    1. Is there a chemical test to identify an ester (Non-spectra based)? This was one of the questions on an HSC paper, and they don't indicate any other than smelling it, so I assume not 2. The oxidation of an aldehyde to form a carboxylic acid has to be done with an acidified oxidising agent, so...
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    Dipole-Dipole vs Hydrogen Intermolecular Bonds

    Apologies for questions, probably been answered before, just having a bit of a pre-HSC panic. 1. How come the intermolecular bonds formed with a carbonyl group on a molecule (i.e. carboxylic acid, or the non-carbonyl oxygen in the ester group) is defined as forming a dipole-dipole bond, but the...
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    Good Schools for Past Papers?

    Did anyone have any schools that they thought the trials papers for were difficult? I'm looking for Phys, Chem, 4U and 3U math (The schools I've looked at are Ruse, Baulko, NSB and Sydney Grammar) Thanks
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    Wouldn’t the light wavelength decreases as the solution would have absorbed it?

    Absorbing the light doesn't make any change to its wavelength, rather it changes the intensity (If you study Physics the difference is a bit easier to conceptualise, as the energy of the photons is the same, but the number of the photons reduce). A is right because the detector and the lamp...
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    HSC Advanced Mathematics Predictions / Thoughts

    I'm not sure how right the answers are, seeing as it says 2 for 10 (MCQ) when it's 3, so dw. I haven't checked the other ones though
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    What is this technique??

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    1984 and Fahrenheit 451 as Related Texts

    Does anyone have any suggestions for resources available to use Fahrenheit 451 as a related text for 1984? Also, for people who did study 1984, were there any other books that were particularly useful as a related text? (Given we are studying love in 1984 rather than control/power) Thanks
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    De Moivre's Theorem

    Thanks guys - turns out I just pulled a bit of a dumb :) Out of curiosity, does anyone have any ideas to prove the sum of cosine expression I thought I needed?
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    De Moivre's Theorem

    Not sure how to solve the following: (1+cos(a)+isin(a))^k+(1+cos(a)-isin(a))^k = (2^k*2)*cos(ka/2)cos^k(a/2) I can get it down to proving: 1 + cos(a) + cos(2a) + .... cos(ka) = 2^k*cos(ka/2)cos^k(a/2) But don't know where to go from there. I'm almost certain you need to use: 2cos(A)cos(B) =...
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    Places to find harder proofs questions (~extracurricular/olympiad type)

    I'm not sure but is this even true? Just subbing in a=1, b=2, c=3, d=4: x = 2.5 = 1.5 * 0.5 * -0.5 * -1.5 Which isn't 4? Unless I'm understanding the question wrong here