From: Alberto Novo (alnovo@inwind.it)
Date: 03/23/01-03:51:00 PM Z
I am wondering if my previous messeges were posted in this list or not.
As I told yet, vols means "volumes of oxygen that one volume of an hydrogen
peroxide solution can yeld". It is an obsolete measure unit, but still used,
I tink, only for tradition.
About the conversion between vols to % and vice versa, one can use a factor
of 3.4 (1% = 3.4 vol) in the range 0-20vols. At higher concentrations the
increase of the density (kg/dm3) of the solution lead to slightly different
conversion constnts.
If the list is interested in a more extensive information about the
different conversion among the measure unit (like, for example, percentage
by weight or by volume, and so on) let me say.
Alberto
-----Messaggio originale-----
Da: Jack Fulton [mailto:jefulton1@home.com]
Inviato: venerd́ 23 marzo 2001 18.54
A: alt-photo-process-l@sask.usask.ca
Oggetto: vols of peroxice
I was interested in the hydrogen peroxide measurement conversation and
wondered what vols meant etc. So I found a site on conversion and Frank
Tapson from the UK wrote me back w/this info . . .I hope it helps us all
but, I admit, it is still a wee bit confusing
Jack Fulton
>I am wondering about a unit of measurement regarding %'age in the strength
>of Hydrogen Peroxide. I am on a photography listserve where we discuss uses
>of chemicals and recently many have been mentioning vol or vols.
>
>One person said an article said that: "article calls Hydrogen Peroxide
>20vol equivalent to 6%" and none of us know what that measurement means.
Hydrogen Peroxide is H2O2 and is a very dangerous substance in its 'pure'
form.
So in normal use it is diluted with (pure) water. The strength of this
solution is shown in two ways.
One is to give the percentage of HP in the solution and so a 6% strength
would have 6 parts HP to every 100 parts of the solution.
The other is in the form of a statement like '20 vol' which means that it
will produce 20 times its own volume of oxygen gas.
I have no idea whether 20 vol is the same as 6% though presumably such
knowledge is available somewhere. Any pharmacist would know.
This archive was generated by hypermail 2b30 : 04/02/01-09:55:26 AM Z CST