Recent content by kmichel1985

Thanks for the help. I just used the calculator and got the same result. Someone else told me I could use Henderson-Hasselbach, but in that equation do I also use the intermediate pKa? This person told me to: 1.) assume that all the HCl is reacted with the bicarbonate to form H2CO3 2.) assume...

This should be an easy one for some of you, but it's difficult to me because of my lack of chemistry knowledge. This is not a homework problem, but a calculation I need to do for my research. I need to calculate the pH of a 1 Liter solution containing 0.000077 M HCl and 0.03 M Na-HCO3. (not...

Thanks Mike, I found these pumps here, which I think you're referring to? http://www.mcmaster.com/#vacuum-pumps/=fl8kek I personally like pump C, at 0.5 cfm at 28" Hg. However, since I'll be running this thing for a long time I don't think any compressed air tank will last that long. On...

Just to clarify, I'm looking to maintain a constant vacuum pressure over many days of operation. I don't expect significant volumes of air to leave my device, maybe 5 microliters per hour from the water inside because small air bubbles don't appear too often. When a bubble flows through the...

I'm doing work in microfluidics, and need help selecting a vacuum pump as I have no experience in creating or controlling a vacuum. Let me simplify my device: I have water confined between two plates. One of the plates has a hole, covered with a small patch of material that let's gas through...