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    electron configuration

    Correct me if I'm wrong, but I think this has something to do with Schrodinger's model? (That was covered in year 11, not HSC chemistry.) Bohr's model stated that there was a maximum number of electrons which can occupy any given electron shell/energy level - which is where your 2n^2 comes into...
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    equations for "recent discoveries of elements"

    There are actually a few that are more recent than that - Ununtrium - Wikipedia, the free encyclopedia Ununtrium (Z=113), synthesised in 2003-2004. Ununpentium - Wikipedia, the free encyclopedia Ununpentium (Z=115), synthesised in 2004. But hassium and bohrium as mentioned by...
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    Chemistry tutoring! HSC Mark = 97

    Chemistry mark twins, whoo! Well done on the great marks/UAI btw, you must be stoked :p
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    State ranking for Biology

    ... Ok this is weird. I know someone who's external was 97, internal was presumably 96 and final HSC mark was 97. They got a state ranking. I wonder why?
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    Should I pick up Senior Science?

    Ok so senior science does scale pretty badly, but to anyone who genuinely enjoys science, I say go for it. It's definitely not going to stop you from getting a high UAI if you do well in it. I got a UAI of 99+ and senior science was included in the calculation of my UAI. Just choose things...
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    Accessing accuracy of secondary information

    The following was taken from this site: http://webs.mn.catholic.edu.au/physics/emery/accuracy.htm I think accuracy is confined to first-hand investigations. See outcome H12 in your syllabus - it says evaluates ways in which accuracy and reliability could be improved in investigations. So...
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    Production of transuranic elements and radioisotopes - different?

    Both transuranic elements and radioisotopes can be produced using nuclear reactors AND high energy particle accelerators. So in a way, no, there isn't a great difference between their production. It just depends on the specific transuranic element or radioisotope being produced. For example...
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    Chem assesment task one part 2. Help would be appreciated

    Podium and stratium aren't elements... And I'm not sure about the uses of uranium, or if it's used in industry at all, but it's not the 'ideal' one to use for an example of an industrial radioisotope in HSC chemistry. Also I'm not sure about carbon-14 either, but it's best to pick a common one...
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    help needed

    ^ What gurmies said. Read the question carefully and know what you're being asked to find. Learning the 5 basic formulae required in HSC chemistry is also a good idea. n=c.V (moles = concentration x volume) n=m/M (moles = mass divided by molar mass) n=V/Vm (moles = volume divided by...
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    rαdiαctive isotopes? ><'

    Re: rαdioαctive isotopes? ><' There are many radioactive isotopes used in industry and medicine, for example cobalt-60 is used in industrial radiography to detect defects in metals. Technetium-99m is a radioisotope used in diagnostic medicine, to pinpoint brain tumours and trace abnormalities...
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    Enzyme use for PLA???

    Lactobacillus bacteria or a type of fungi called 'rhizopus oryzae'. Neither are "enzymes" though. They're microorganisms. (Read the syllabus dot point closely – it says enzymes OR microorganisms'.) Steps in the synthesis of PLA: 1. Corn or sugarcane is milled to extract the starch. 2. Dextrose...
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    Chemistry tutoring! HSC Mark = 97

    Thanks Ashna! Even though I caved under the pressure in the actual HSC... I made the silliest mistakes, honestly. :( You should also consider doing some tutoring yourself, seeing as you consistently owned all of us in English. :D
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    Chemistry tutoring! HSC Mark = 97

    Hi everyone, My name is Anna & I will be tutoring preliminary and HSC chemistry (+option: industrial chemistry) now that the HSC is over. :D I came first in chemistry this year at Hurlstone Agricultural High School, ranking first in all 4 assessment tasks throughout the year. My marks...
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    Question 18 from 2008 exam

    No, it's not in the HSC course. I think we did this in year 11 - when we were learning something to do with trends in the periodic table? Anyway: "Down a group, the metallic character increases, due to the lesser attraction from the nucleus to the valence electrons (in turn due to the atomic...
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    Question 18 from 2008 exam

    From memory, I think the more metallic an element is, the more basic its oxide. And elements get more metallic going down groups. Therefore, the going down a group, the oxides of elements should get more basic. Same theory applies for acidic oxides. I'd also mention the fact that the elements...
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    Stronger acid

    My guess is that H2SO4 and HCl are equal in strength... They're both strong acids and neither is 'stronger' than the other, according to what 'strength' is defined as in the syllabus (although I agree that H2SO4 would have a lower pH when both are present in equal concentrations). Since...
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    red cabbage indicator experiment

    Ok thanks :) I'm going to go with the results I have, since it's pretty similar to the macquarie book.
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    Questions

    http://en.wikipedia.org/wiki/Equilibrium_constant#Temperature_dependence The reason why the temperature dependent nature of K was always simplified to "energy considerations." And why we were told not to question it. :p
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