shipwrecks...rate of corrosion (1 Viewer)

[stef.]

when re-telling your experiment about rates of corrosion...when measuing, we normally go weigh it before n after etc...but what is it that we are weighing..what is the supposed mass lost?

Fe(s) -> Fe2+ + 2e-

everything should still be in that test tube??

 

[mitochondria]

I think you are referring to weighing the electrode/the piece of iron that is corroded but NOT the entire test tube.

As the equation you have post shows that Fe is lost by oxidation in rusting, therefore the piece of iron you have in the test tube will lose weight =) And by working out the mass difference you can work out many wonderful things (lol) such as the amount of Iron reacted... etc. And they are very useful for doing the HSC *inserts sarcasm*

Actually, you can go about weighing the test tube and find an increase in mass (if you let the rusting to undergo for a long time...) The increase in mass will be the mass of oxygen...

Prone to error since it's 01:00.. Hope that helps though

 

[Abtari]

lol, due to increase in mass of oxygen... oooooh

ummm, one question related to this:

to what extent do we need to know the results of pracs in chemistry (and even physics), especially shipwrecks, where there are soooo many experiments... huh, huh? i mean like the different values of masses of nails, mass decrease, blablabla

 

[serge]

to what extent do we need to know the results of pracs in chemistry (and even physics), especially shipwrecks, where there are soooo many experiments... huh, huh? i mean like the different values of masses of nails, mass decrease, blablabla

If by results you mean numerically?
(you dont need to know anything)

But otherwise, I think you need to know the trends

 

[Abtari]

sweet. thought so.

 

[mitochondria]

Maybe your brain is missing a mathematical department for chemistry?

Not that I ever said you need to remember anything numerical... At least not to you

 

[stef.]

I think you are referring to weighing the electrode/the piece of iron that is corroded but NOT the entire test tube.

so you would take the electrode and scrape off the rust and weigh it right??

 

[Abtari]

yes. you woulddo that.