AAS (1 Viewer)

[girlworld_club]

Exactly how much detail are you supposed to know about AAS for hsc chem.
I had a look at conquering chemistry and the types of questions are on calculations which are difficult. However, i have yet to see a hsc exam with very difficult calculations involving AAS.

 

[girlworld_club]

i am also having problems with question 31 pg 224 of conquering chemistry hsc on sulfate experiment.

 

[golgo13]

I don't have the book on me but generally the ASS component is good in terms of knowing theory like how it works why is it used etc, i think there is probably more theory than calc questions on it (dunno if the styling has changed). The HSC questions are good to work off, if you have more recent trial papers they are good to work on, but usually AAS is limited in the questions when i was doing it, not sure if that has changed

 

[HeroicPandas]

"To determine the sulfate concentration in a liquid fertiliser (aqueous solution), an
analyst first diluted 50 mL of the fertiliser solution to 250 mL, pipetted out 25 mL of
the dilute solution, added 200 mL water to it then precipitated the sulfate with barium
nitrate solution. The precipitate was filtered, washed and dried to constant mass.
In repeated experiments the mass of precipitate was 0.728 g, 0.773 g, 0.722 g and
0.732 g. As accurately as you can, calculate the percentage sulfate in the original
fertiliser solution. Justify the procedure you followed."

I asked a friend with this textbook, gave him the location of the question and he gave me the question. so here is the question if anyone wants to try it out (i cbb)

 

[girlworld_club]

Thanks for posting it so others can see.

 

[girlworld_club]

having problems calculating ppm.

e.g convert 0.93% (v/v) of Argon to mL/kL

how would you do this, i normally solve these questions by using ratios so if you can do it that way it would be great. Also is mL/Kl the same as ppm? i though ppm was mg/L

 

[Sopa]

I totally agree that the AAS questions in the book are hard
i'm having lots of trouuble with #34 on pg 231
if anyone can help, it would be great, i read in this post that, detailed calc. knowledge is not required, but just for that peace of mind

i've uploaded the question on this thread
http://community.boredofstudies.org/showthread.php?t=306427