Specific Gravity of Propylene Glycol

[Morrey]

I have a partial gallon jug of glycol and cannot remember if I have already diluted it with water to make a 50/50 ratio. I assume I can use a floating hydrometer and read the SG to see if the glycol is already diluted?

If I can test with this method, what SG should I read if the glycol was cut 50/50 with water? Or what is the SG range if the glycol is straight up? Is this reading temp dependent?

Thanks for the help....I'll do better labeling the jug next time!

 

[Silver_Is_Money]

About 1.041 for 50/50 with water (by volume). But only about 1.036 when 99+% pure. Determining where it stands may prove to be a bit problematic.

 

[Morrey]

Ok great. It reads almost 1.040 so I know this is diluted glycol. Thanks!!

 

[ajdelange]

Is it syrupy? Put a few mL in a glass and add a like amount of water. Does it get hot? Does the SG stay about the same? If the answer to all these questions is "Yes" then it is near 100%. If it's not syrupy and/or if it doesn't get hot when water is added or if the SG drops to about 1.020 when water is added then it's about 50/50.