Glycerol: v/v or w/v?
Frank O. Fackelmayer
Frank.Fackelmayer at uni-konstanz.de
Fri Feb 25 04:55:23 EST 2000
Wolfgang Schechinger wrote:
> No. Not obviously. I use w/v. Did you ever try to pipet 100%
> glycerol? For this reason, one always should how the dilution was
> In real life, it normally should not matter. What matters more is,
> that there is a difference if you have 50 ml of glycerol and add
> water q.s. 100 ml or if you have 50 ml of water and add glycerol q.s.
> 100 ml. For understanding this phenomenon, mix 50 ml of ethanol
> **and** 50 ml of water in a graded cylinder (the experiment is easier
> to perform with EtOH).
just did it, just for curiosity. Adding 50ml water to 50ml EtOH gave
100ml, adding 50ml EtOH to 50ml water also gave 100ml.
What difference should I see? Why?
PS: I always use v/v for glycerol solutions. w/v is certainly also
correct, although the solution will be less concentrated then. Why not
simply state (v/v) or (w/v) in your protocols to make things clear?
More information about the Methods