Sciencemadness Discussion Board

Tin solder

guy - 27-7-2004 at 23:21

I tried to dissolve some lead-tin solder in a combination of H2O2-acetic acid. There was white stuff coming of it and settle as a precipitate (tin oxide?). Anyways, I dont beleive any lead was dissolved because when I added NaCl no ppt formed. So I added the rest of the solution to NaOH. It turned red and later turned to a light orange peach color. What is it? Is it a tin hydroxide, if so is it Sn(OH)4 of Sn(OH)2? I have searched on google but did find out the color of tin hydroxides. I just want to be sure.

thanx.

The_Davster - 28-7-2004 at 10:02

Coincidently, I am currently dissolving some lead in acetic acid/H2O2. However when I add NaCl I do get a flaky white ppt. I also have a white insoluble solid at the bottom of the beaker but I think that it is lead oxide. It does not seem to react with more acetic acid to give lead acetate.

I have worked with Sn/Pb solder before. Here is a thread in which some experiments with solder were documented.

guy - 28-7-2004 at 10:20

Also something wierd happened.

>When adding NaOH to the solution, it turned red for a second and instantly turned white.

>When adding the solution to NaOH it remained red-orange

The ppt couldn't be Pb hydroxide right? I read that a normal hydroxide does not exist.

Antman 762 - 6-10-2004 at 23:06

is it flux free, if it has flux what your probally seeing is zinc chloride.