Finding the amount of copper in brass methods?

rad95

Can you suggest two or more methods for finding the amount of copper in brass? :smile:

Reply 1

Mounam

Iodometric titration and spectrophotometric analysis.

Reply 2

rad95

OP

@Mounam thank you, I already know how to do it one way which is the Iodometric titration, do you have anymore methods, that would be amazing from you :biggrin:

? thank you!

Reply 3

Mounam

Original post by rad95

@Mounam thank you, I already know how to do it one way which is the Iodometric titration, do you have anymore methods, that would be amazing from you :biggrin:

? thank you!

There is an alternative method based on density that is to find the ratio of a substance's mass to the volume of space it occupies which is cheaper than other 2 methods.

Reply 4

ECDawson

I just started A2 Chemistry (on the OCR Salters B course) and we were told that we have to do Individual Investigations for our coursework. I'm still looking over the different suggested topics and I'm looking into the "Amount of Copper in Brass" topic, although if anyone has any suggestions that might prove more straightforward I'd be very appreciative!

I just wondered if anybody has done this coursework and what sort of approach you think I should take towards it. The possible aims says: "Compare different methods for finding the concentration of copper(II) ions in solution. Could include redox titration, colorimetry, ion exchange followed by acid/base titration, gravimetric, use of an electrochemical cell."

A girl in my school looked at pennies and compared two types from different eras... I think that's really imaginative but obviously I can't copy it! Any suggestions would be lovely, thanks! :smile:

Reply 5

shengoc

12

Original post by ECDawson

I just started A2 Chemistry (on the OCR Salters B course) and we were told that we have to do Individual Investigations for our coursework. I'm still looking over the different suggested topics and I'm looking into the "Amount of Copper in Brass" topic, although if anyone has any suggestions that might prove more straightforward I'd be very appreciative!

I just wondered if anybody has done this coursework and what sort of approach you think I should take towards it. The possible aims says: "Compare different methods for finding the concentration of copper(II) ions in solution. Could include redox titration, colorimetry, ion exchange followed by acid/base titration, gravimetric, use of an electrochemical cell."

A girl in my school looked at pennies and compared two types from different eras... I think that's really imaginative but obviously I can't copy it! Any suggestions would be lovely, thanks! :smile:

assuming your brass is pure and only contains zinc and copper, how can you use chemical reactions to quantify how much there is of one of them, leaving the other unreacted; ie if i have 1 g of brass, if x g of the Zn undergoes this reaction which Cu doesn't, then that means the unreacted amount = (1 - x) g would be Cu, provided all Zn reacts of course. The same idea could work if you have a rxn that only involves copper but not zinc.

I hope you see the amount of variation you can do here - hence a practical investigation. Propose a hypothesis, put it to trial based on good evidence it might work, then observe and analyse what happens. :smile:

Reply 6

Mohid Khan

14

I also need help with this investigation, We have to do 12 hours of practical work, but i only have a few experiments (which i can complete in 4 hours Max) so can i get some advice.
And also some general guidance on how to write my essay.

Thanks in advance

Reply 7

Borek

4

I would start with any serious classic analytical chemistry book - it should contain many methods (gravimetric, titrimetric) to choose from. Brass analysis is a standard thing, discussed to death.

Sorry, no idea about which book will be best, although I can suggest several in Polish :wink:

Reply 8

Mohid Khan

14

Thanks, i shall research some books.

Also does anyone have a good example of a risk assesment, because i cant THINK of any thing different for each chemical. its the same boring "Irritant/ corrosive/ harmful" and to avoid this wear gogles gloves and lab coat"

Reply 9

Nirgilis

14

Original post by Mohid Khan

Thanks, i shall research some books.

Also does anyone have a good example of a risk assesment, because i cant THINK of any thing different for each chemical. its the same boring "Irritant/ corrosive/ harmful" and to avoid this wear gogles gloves and lab coat"

Look up each chemical on Sigma Aldrich website. Each chemical will have a ''Safety and Documentation'' section, which tells you the hazards and risks.

For example, benzene:

http://www.sigmaaldrich.com/catalog/product/sial/319953?lang=en&region=GB

and the hazard and risk codes can be found here:

http://www.sigmaaldrich.com/help-welcome/hazard-and-precautionary-statements.html#hazard

Reply 10

Borek

4

To add to Nirgilis post: you can always google for "substance name MSDS". MSDS stands for "Material safety data sheet", and there are plenty of these on the web, as every company selling chemicals is obliged to provide information about the product in the form of MSDS.

For sure these searches will lead you to - between others - Sigma Aldrich site.