Sciencemadness Discussion Board

hydrometer scales

Swede - 11-12-2008 at 08:31

My friends at APC didn't answer this one; I'm sure someone here can do it: BTW, I am very embarrassed that I don't know what it is. I did search google a bit with no luck.
Quote:

I can't understand one of the two scales on my hydrometer! Checking some acids with a hydrometer, and the acid came in at 1.35 SG. There is a second scale, parallel to the first, which read 1320. WTF? What's the second scale? On the instrument itself, at SG = 1.00, the mystery scale reads 1000. At 1.24, its 1200; 1.54, 1600. At 1.70 SG, the second scale is 1950. I surrender... what is the second scale?


Can anyone identify the second, "mystery" scale on this hydrometer?


[Edited on 11-12-2008 by Swede]

hissingnoise - 11-12-2008 at 09:08

It's a long-shot, but would the second scale measure density at a slightly higher temperature.
My hydrometer (alas) has only one scale.

Ozone - 11-12-2008 at 09:10

A simple list of the various scales is given here:

http://www.sizes.com/units/hydrometer.htm

My guess is that your mystery unit is kg/m3.

Cheers,

O3

[Edited on 11-12-2008 by Ozone]

Saerynide - 11-12-2008 at 22:31

Hmmm... Plain kg/m3 doesnt make sense. At 1.7 sg, that would be 1700 kg/m3...

Perhaps it is at a higher temp AND in kg/m3 :D

[Edited on 12/12/2008 by Saerynide]