Measuring KOH concentration with hydrometer

[BoyntonStu]

Specific Gravity of KOH :

27% = 1.2592
28% = 1.2695
29% = 1.28
30% = 1.2905


BoyntonStu

More complete table here: http://www.ashtachemicals.com/products/kohchem.htm#sg

[computerclinic]

Good info boyntonstu...I was wondering that...

[Roland Jacques]

Thats good info . now all we have do is fine a hydrometer or Refractometer that can read that range.

[Roland Jacques]

Any luck on finding a hydrometer that can read these ranges.

I found these, I think the lower one should be OK. http://sciencekit.com/hydrometer/p/IG0023641/

[Roland Jacques]

Is it 28% by weight the Ideal concentration?
If so would 0.5 lbs of Noah or KOH and 1.0 lbs of water = 33% concentration?

[hg2]

Is it 28% by weight the Ideal concentration?
If so would 0.5 lbs of Noah or KOH and 1.0 lbs of water = 33% concentration?

28% is ideal for most dry cells,but an openbath type would overheat quickly and the amps would spike high as well.I use 33% in my dry cell which works out to over a pound of koh per gallon distilled water.
I think the hydrometer you mentioned is the same that saltwater aquarium owners use to test salt content in their tanks