[lalala]

hi i have a problem that apparently involves a back titration method to solve it..
i need to find the thickness of a metal zinc foil without using a ruler or and scale.so meaning, i need to find out the thickness throught a chemical method.
the known density of this zinc metal foil is 7.13 g/cm³
i need help forming a method to calculate the thickness of the zinc foil.

[Borek]

without using a ruler

IMHO impossible. And I don't mean using ruler to measure thickness.

[enahs]

V = l * w * h

d = m/V -> V = m/d

m/d = l * w * h


Come up with a chemical reaction to determine the amount in mols, and thus mass, of the aluminum foil.


Your question says find thickness; but there are three dimensions to any real object. Are the other two dimensions given/assume you know them? Other wise, the only way I see off hand in determining the area of the foil would require some really complex kinetic studies. Maybe I am wrong though.


Also note, you will have to be extremely careful with your units.

[billnotgatez]

One could measure length and width then weight the sample. Thus the thickness could be derived. This appears to be forbidden for this problem.

Can you do  just measuring and not weighing?

[Borek]

Your question says find thickness; but there are three dimensions to any real object. Are the other two dimensions given/assume you know them? Other wise, the only way I see off hand in determining the area of the foil would require some really complex kinetic studies. Maybe I am wrong though.

If you are wrong - welcome to the club

[billnotgatez]

My first thought was that this was a nonsense question. I will give an example.
Question –
Your are in a room and you have nothing. How do you get out of the room?
Answer –
You look around the room and see what you saw.
You take the saw and cut a hole in the wall and escape.


My second thought was to try to deduce the size of the zinc. You could cut it in a square and take a measurement that is based length alone (Maybe conductance). You derive the length from that measurement. Since the item is square then you have the length and width. Do your titration to determine the number of moles. Derive the weight from the number of moles. Then derive the thickness based on density and volume. This is as about a wild a guess as anyone could make. No one else would make this guess because they know better, but someone had to fall on the sword.

[billnotgatez]

is this a double post

http://www.chemicalforums.com/index.php?topic=18441.0