One US ounce = 29.57353 ml. Thus 43 ml is almost an ounce and a half. Marshall
Ian Roe wrote: > Hi: A 500 ml container has 16.6 oz in it. I already know that if 1oz > of 35% is added to 11 oz of distilled that a 3% results but you > indicate that adding less than an ounce to 500 ml would give me 3%. > Adding less than an ounce to 16.6 oz would give an even weaker > solution wouldn't it? Ian ----- Original Message ----- > > From: Marshall Dudley > To: silver-list@eskimo.com > Sent: Tuesday, December 03, 2002 3:37 PM > Subject: Re: CS>Titration Math > Ian Roe wrote: > > > Hi: I'm not the greatest when it comes to titration > > mathematics. Can someone here show me the formula for > > dilution. I knew how to do this once but I just can't > > remember now. Problem: wish to put an unknown volume of > > 35% H2O2 into a 250 ml and a 500 ml container and fill > > with distilled water to obtain 3%. > > That is pretty easy. You want 500 ml of 3% H2O2, so you > > want the container to contain .03*500 = 15 ml of H2O2 with > > the remainder water. Since the H2O2 is 35% to start with > > you will have to start out with 15/.35 ml of the 35% H2O2 > > or just under 43 ml. > > > > So put just under 43 ml of your 35% H2O2 in the 500 ml > > container, and fill with water to 500 total volume. Now > > that will be a volume percentage. For a weight (mass) > > percentage, then you would have to work with weights, but > > I think the 35% H2O2 is close enough to the mass of water > > to not worry about it. > > > > Marshall > > > > > > Equipment: 35% H2O2, 250 and 500 ml containers and a 30 > > ml measuring cup divided off in 5 ml lines, drams at the > > 1/4 oz markers, 1/4 oz markers - and of course distilled > > water. Thanking you in advance. IanRoe >
