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Answers To Difficult Questions (3 Viewers)

jbai

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Look at wiki article for "catalyst", chlorine is a catalyst.

No.9 is A, Citrate = Conjugate Base of Citric (weak) acid.
 

mat2154

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nooj said:
14 is d, b is talking abt atomic emission
its definitely not a
i don't think its c cause it says "white light" should be "light of a specific wavelength"
probably is d

plus the silly mistake i made in the exam should get 13/15 in multi choice
 

Martyno1

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Pyros89 said:
But its called atomic absorption spectroscopy
Well I don't know we may be right but so many people seem to have put D heh. And if the sample is vapourised in the flame.. and that's not meant to be enough to excite the electrons.. I dunno
 

Pyros89

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Martyno1 said:
Well I don't know we may be right but so many people seem to have put D heh. And if the sample is vapourised in the flame.. and that's not meant to be enough to excite the electrons.. I dunno
True, but my teacher said the purpose for the flame was to make it into a gas, cause it doesn't work as solids.
 

Martyno1

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Bank$ said:
ohh gud then im safe lol damm now im definate i got the ppm one wrong i hope they mark like maths and c that i had the right working out lol

EDIT: if i did that is lol
Yeah I hope they do the same for the sulfur ppm question and give me at least a mark, gee I think I deserve it lol. :p
 

Bank$

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Martyno1 said:
Yeah I hope they do the same for the sulfur ppm question and give me at least a mark, gee I think I deserve it lol. :p
haha same for me dam and i thought i would do well in calculations lol
 

Bank$

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so yeah if any1 remembers what they got for the bottle question (precipitate one) pls write down :)
 

JoshyPutts07

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sorry guys, pretty sure that AAS one was C.........B is wrong as "vaporised atoms falling down to their ground state" sounds bit more like chemiluminescence, and for AAS why would they need to fall donw to their ground state anyway?, C was most logical
 

Martyno1

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JoshyPutts07 said:
sorry guys, pretty sure that AAS one was C.........B is wrong as "vaporised atoms falling down to their ground state" sounds bit more like chemiluminescence, and for AAS why would they need to fall donw to their ground state anyway?, C was most logical
thank you jesus :D

i also remembered (from software design and development.. lol) that white light has every colour in it. so yeah that's what helped me with my choice of C.
 

Bank$

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JoshyPutts07 said:
sorry guys, pretty sure that AAS one was C.........B is wrong as "vaporised atoms falling down to their ground state" sounds bit more like chemiluminescence, and for AAS why would they need to fall donw to their ground state anyway?, C was most logical
bro im sure its d cause the light is white and it has to match the spectrum of what u messure
 

imraan7860

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white light contains all wavelengths of light so if a sample absorbs a specific wavelength itll absorb one form the white light.

Wat were ppls order for the aqueous solutions i think it was q18
 

Martyno1

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imraan7860 said:
white light contains all wavelengths of light so if a sample absorbs a specific wavelength itll absorb one form the white light.

Wat were ppls order for the aqueous solutions i think it was q18
1 was Na2CO3
2 was HCl
forget the order of the rest
 

nooj

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c is incorrect beacuse they change the lamp depending on the metal being tested look in your text book, its there
 

!!!akittelty!!!

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No need to be sorry joshyputts. cos the answer is d.
white light isnt used in aas. they only use the one wavelength and measure how much of that is absorbed. otherwise other elements would interfere with results. the wavelength they use is the one that the specific element absorbs, the same one it emits in a flame test.
 

Martyno1

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nooj said:
c is incorrect beacuse they change the lamp depending on the metal being tested look in your text book, its there
Well it can't be D because the flame test doesn't have enough energy to excite the atoms to release a wavelength (or does it?)..
 

Bank$

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Guys we all smart so dont worry we all do well lets concentrate on the exams ahead !
 

imraan7860

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well thats another few marks i lost, i had the cabonate and sumthing else def not HCl.

Hmmm wat else wat were the things of chlorine, its needs to be monitored, apprently its sumthig to do with salinity, i only wrote to kill microorganisms cept cant be too much
 

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