gravimetric analysis problem (1 Viewer)

[**freakstar87**]

heya in chem my class has this task where we have to do a scaffold on a practical experiment on gravimetric analysisusing this aim
to carry out a gravimetric analysis of a solid mixture of sand and copper sulfate
and since the aim is provided we only need to do the apparatus, diagram, method, table of results, explanations of calculations required and safety precautions.
i really need to know what type of physical separation process i need to perform in an experiment like this, what apparatus i need to use and what type of data i need to put on the table as heading for the result. so plz if you know how to do this, it will be grateful! if you know more about on what to write on how to set up this experiment (method) it would also be very much needed. thanks!

 

[Affinity]

crystal picking (ie, picking the copper sulfate crystal out of the mixture with a magnifying glass) J/K

Ok.. what you do here is filtering, because it's a mixture of one thing that dissolves in a common solvent(water) and another which doesn't.

ah and you only need to weigh the original mixture and the sand (don't need to weight the copper sulfate).

what I will do is weigh mixture, the wash/filter it a few times keeping the sand, dry the sand and weigh it.

 

[kimmeh]

i'm suprised they didnt teach you baisc prac writing in year 10
but as affinity said, filtering is the way to go. add water, filter and let evaporate
you might like to weight the filter paper before you start filtering it so you can find the mass of the sand more easily by taking the final mass minus the mass of the filter paper.

 

[**freakstar87**]

we did get taught basic prac writing. the only problem is that some of the science teachers i have so far said to write the method in past tense and others tell me to write in present tense so i got really confused now.

EDIT: also my chem teacher didn't give us enough info about gravimetric analysis except the definition of the process and a few examples of it but that's all.

 

[Constip8edSkunk]

ffs... who cares about tenses in high school chemistry reports?

 

[Xayma]

Originally posted by Constip8edSkunk
ffs... who cares about tenses in high school chemistry reports?

And english creaps more and more into HSC sciences.

 

[kimmeh]

Originally posted by Constip8edSkunk
ffs... who cares about tenses in high school chemistry reports?

depends who your teacher is really, i know some of my teachers prefer past tense and other prefer it as a method. rather odd though what do the HSC markers prefer ?

 

[*girl04*]

hmmm we did grav. ana of salt sand n water

 

[CM_Tutor]

Originally posted by Constip8edSkunk
ffs... who cares about tenses in high school chemistry reports?

Just FYI, the correct way to write up practical methods is in the third person, past tense, passive voice. This is the scientific standard and would be expected at Uni. I would advise that you write up this way unless your teacher objects - you may as well get used to doing things the correct way in the first place.

 

[xiao1985]

lolz... thx for ur advice cm_tutor... heyz, u a uni lecturer?? or uni student?? or school teacher?? or none of above??

 

[CM_Tutor]

Originally posted by xiao1985
lolz... thx for ur advice cm_tutor... heyz, u a uni lecturer?? or uni student?? or school teacher?? or none of above??

PhD Student, studying Chemistry Education full time, and doing a Masters degree in Education (in Teaching and Curriculum Studies) at the same time. I also get to 'help' with theses, and I'm still correcting methods that are not written according to the above rule!

 

[sikeveo]

nice!!! i wouldnt mind teaching for a bit, but then my parents would laugh

 

[xiao1985]

Originally posted by sikeveo
nice!!! i wouldnt mind teaching for a bit, but then my parents would laugh

lolz... ur parents r means... =p blehz

Originally posted by CM_Tutor
PhD Student, studying Chemistry Education full time, and doing a Masters degree in Education (in Teaching and Curriculum Studies) at the same time. I also get to 'help' with theses, and I'm still correcting methods that are not written according to the above rule!

dat's coolz.. which uni??

 

[CM_Tutor]

Originally posted by xiao1985
dat's coolz.. which uni??

USyd

 

[Lexicographer]

Wow! We haven't done this stuff at uni yet. Maybe we're skipping it, or haven't reached it yet.

 

[kimmeh]

Originally posted by Lexicographer
Wow! We haven't done this stuff at uni yet. Maybe we're skipping it, or haven't reached it yet.

maybe you did it in your bridging course and was too busy getting onto PM
its not that exciting, gravimetric analysis anyway. you're not missing out on anything really.