[alt-photo] Re: Math mystery

[Kees Brandenburg]

> So, when using a 37% solution of formalin, I would think that you have to
> use around 80ml of the formalin solution...

Jacques,

Formalin is a 37% solution of formaldehyde gas in water. This is considered as full strenght (= 100%) formalin. If a recipe asks for 25ml undiluted formalin in 1 liter water this is  a 2,5%  formalin solution. Your correction by adding 80ml instead of 25 ml to compensate for the 37% formaldehyde solution in formalin is wrong. You end up with a too strong mix! 

Anyway I should try to avoid formalin alltogether.

Kees