[orgo814]

What would be the best way to prepare 20 micromolar solution phosphate buffer. I'm returning to this kind of chemistry after a bit so a little rusty.

So if I started out with a 0.1 M buffer solution, I remember the equation M1V1 = M2V2. So (0.1) (10 mL) = (mL) (2.0x100^-7).

After solving for the volume I need, do I just dilute it with water with whatever volume I solved for and that will give me the concentration? So confused!

[Hunter2]

You have 0.1 M = 100 µM Solution. To get a 20 µM solution what you have to do?

[Borek]

After solving for the volume I need, do I just dilute it with water with whatever volume I solved for and that will give me the concentration?

You dilute not WITH the volume calculated, but TO the volume calculated.