I think I will be adding a 5000ml volumetric flask to my equipment. The reason is that now that I am using muriatic acid, the cost of the supplies becomes negligible, so I can increase the testing frequency with very little added expense. However, increasing the testing frequency will increase the need to mix up new 0.02N reagent more often. The solution is to mix in larger volumes. I have been using 1000ml volumetric flasks for the mixing in the past, so mixing in larger volumes requires multiple mixes during the same re-fill procedure. This adds to the effort required, and makes increasing the testing frequency less advantageous.
The solution for this is to use a 5000ml volumetric flask instead of using 1000ml ones. That way I can use 50ml of muratic acid along with 4950ml of RODI to get to 5L of 0.1N, or I can use 10ml of muriatic acid along with 4990ml of RODI to get 5L of ready to use 0.02N.
Amazon has the 5000ml volumetric flasks, but they are not cheap. All the ones they offer are class A, so that explains why they are expensive. I can get a German made class A for $183.65 CAD, plus shipping and taxes. So we can call it $200 CAD. As a one time expense, I think that is reasonable.
I am not sure how large the flask will be physically. The listing shows it's weight as 4Kg, so just under 9lbs empty. So fairly hefty to use I expect.
The flask I am considering it also calibrated at 27C, which is fair bit hotter than I would typically keep the local environment and solutions at. I am not sure how much effect using the flask at a cooler temperature would have. I keep my house (and RODI) at 23C. Hopefully this does not affect the end result too much.
Dennis
