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General thoughts: HSC chemistry 2015 (1 Viewer)

HecticLad

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i wrote about strontium 90, and i dont think it has any disadvantages when using it to detect hardness, but i didnt write explicitly it had no disadvantages, do you think ill lose marks?
Nah fam, in past marking guidelines for discuss questions they always specify it as for and/or against, just whether you had enough information etc.
 

BlueGas

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i wrote about strontium 90, and i dont think it has any disadvantages when using it to detect hardness, but i didnt write explicitly it had no disadvantages, do you think ill lose marks?
I also spoke about Strontium 90 (damn what a sick name) for thickness gauging. I mentioned the disadvantages: Continued exposure blah blah blah, and the waste has to be stored or dumped into ocean blah blah blah.
 

Anousha

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I wrote about Americium-241 for domestic use in fire detectors, the alpha radiation it emits ionises oxygen and nitrogen in the atmosphere, when smoke is present it absorbs the ionised oxygen and nitrogen causing the rate of ionisation to drop and the alarm going off.
- adv long half life of 432 years wouldn't need to be replaced as often .....etc
- disad continuously emits alpha radiation compounded with that fact of having a long half-life that may harm humans in some way ...etc
would that be enough for 5 marks ?:cry: (barely studied for this which I should have ugh)
 

BlueGas

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I wrote about Americium-241 for domestic use in fire detectors, the alpha radiation it emits ionises oxygen and nitrogen in the atmosphere, when smoke is present it absorbs the ionised oxygen and nitrogen causing the rate of ionisation to drop and the alarm going off.
- adv long half life of 432 years wouldn't need to be replaced as often .....etc
- disad continuously emits alpha radiation compounded with that fact of having a long half-life that may harm humans in some way ...etc
would that be enough for 5 marks ?:cry: (barely studied for this which I should have ugh)
Seems abit too short.
 

malcolm21

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I wrote about Americium-241 for domestic use in fire detectors, the alpha radiation it emits ionises oxygen and nitrogen in the atmosphere, when smoke is present it absorbs the ionised oxygen and nitrogen causing the rate of ionisation to drop and the alarm going off.
- adv long half life of 432 years wouldn't need to be replaced as often .....etc
- disad continuously emits alpha radiation compounded with that fact of having a long half-life that may harm humans in some way ...etc
would that be enough for 5 marks ?:cry: (barely studied for this which I should have ugh)
wait, didnt the question ask how is the radioisotope used in an INDUSTRY thats not the medical industry?
 

Anousha

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wait, didnt the question ask how is the radioisotope used in an INDUSTRY thats not the medical industry?
smoke detectors are produced in an industry, unlike Technetium-99m used for medical purposes
 

malcolm21

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^ The guy i quoted said he said americium was used for domestic smoke detectors, if i recall correctly the question said the word industry twice too. isn't 'domestic use' not an industry and if i recall correctly i think it asked for the name of the industry (dont quote me on that)?
 

TQuadded

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^ The guy i quoted said he said americium was used for domestic smoke detectors, if i recall correctly the question said the word industry twice too. isn't 'domestic use' not an industry and if i recall correctly i think it asked for the name of the industry (dont quote me on that)?
Maybe industry = production of smoke detectors?
 

Loudvicuna

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Will i still get marks in the radioisotope in industry question if i wrote sodium-23 which is stable instead of sodium-24?
 

malcolm21

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Will i still get marks in the radioisotope in industry question if i wrote sodium-23 which is stable instead of sodium-24?
I think you might lose 1 or 2 marks, did you talk about sodium 24 the whole way through and just accidentally wrote sodium 23 instead?
 

Anousha

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^ The guy i quoted said he said americium was used for domestic smoke detectors, if i recall correctly the question said the word industry twice too. isn't 'domestic use' not an industry and if i recall correctly i think it asked for the name of the industry (dont quote me on that)?
when we had a topic test in class, there was an extended response question (6 marks) asking to analyse benefits and problems associated with use of radioactive isotopes in both industry and medicine, examples, reference to properties etc.. As an industrial isotope I wrote Americium-241 and I got full marks :))) (my teachers a HSC marker)
 

BillKyriakos

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I only spoke about the properties which make sodium-24 a suitable radioisotope in industry (type of decay, half-life and what it decays to + an equation)? Would that get me the 5?
 

HecticLad

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I only spoke about the properties which make sodium-24 a suitable radioisotope in industry (type of decay, half-life and what it decays to + an equation)? Would that get me the 5?
You would have to write the specific applications of it, and why it is useful for those applications based on its properties
 

malcolm21

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You would have to write the specific applications of it, and why it is useful for those applications based on its properties
what would you think about the people writing about americium. I dont see it having any application in an industry and only the home
 

TQuadded

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what would you think about the people writing about americium. I dont see it having any application in an industry and only the home
Smoke detectors aren't just used in the homes. Chances are that an industry building will have at least one smoke detector.
 

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