ORGLIST: Re: Rafael Velasquez D/troublesome tin oxide

Date view Thread view Subject view Author view Attachment view

From: Jacob Zabicky (zabicky$##$bgumail.bgu.ac.il)
Date: Tue Jun 09 1998 - 05:56:00 EDT



>
>Date: Mon, 27 Apr 1998 21:59:23 -0500
>From: Rafael Velasquez D <ravelasq$##$tunja.cetcol.net.co>
>Subject: Stannic oxide
>
>
>I'm trying to obtain tin oxide from bronze, I treated the alloy whit
>nitric acid and then I separated the precipitate substance by
>filtration. The precipitate substance I supposed that was SnO, its color
>was brown, then I heat it with a burner and I obtain a white bone
>substance, that I supposed that it was SnO2, then I heat it near to the
>600=B0C with the purpose of burn the filter paper, but the substance
>changed to a black color, the filter paper was without ash.
>Who can explain me the change of color and how can I make to obtain the
>SnO2?
>Thanks in advance
>Edwin
>

Hello Rafael,

You are right about what you thought to be tin oxide of various degrees of
oxidation. That's tin. To ensure that you get SnO2 you have to burn the
thing for long hours, whereas to ensure SnO you have to use a good reductor
under contolled conditions. The following "analytical" references are
related to your story and may be helpful:

R Reverchon, Chim. Anal. (Paris), v. 47, p. 70 (1965)
MP Brown and GWA Fowles, Anal. Chem., v. 30, p. 1689 (1958).
JGA Luijten and GJM van der Kerk, in Investigations in the Field of
Organotin Chemistry, Tin Research Institute, Greenford, UK, 1966, p. 84.
T. R. Crompton, Chemical Analysis of Organometallic Compounds, Vol. 3, p.
13 (1974)
R. Geyer and HJ Seidlitz, Z. Chem., v. 4. p. 468 (1964).
V. Chromy and J. Vrestál, Chem. Listy, v. 60, p. 1537 (1966).
J. Zabicky, in The Chemistry of Organic Germanium, Tin and Lead Compounds,
S. Patai (ed.), Wiley, Chichester, p. 365 (1995)

All the best,

Jacob Zabicky


__________________

ORGLIST - Organic Chemistry Mailing List
WWW Homepage and Archive: http://www.orglist.net/
List coordinator: Joao Aires de Sousa (jas$##$mail.fct.unl.pt)



Date view Thread view Subject view Author view Attachment view

This archive was generated by hypermail 2.1.4 : Fri Sep 19 2003 - 12:14:43 EDT