Salt Test NEWB question

[MillhizzelPB]

ok when i am doing the salt test i have the hygo in the sealed bag w/ the salt. the weird thing is the reading changes when i check it from time to time. i have had it in there for about 12 hrs. when i check it from time to time i goes up and down... isn't this test done in order to check how close it is to 70%? dont we seal it in the bag for so long in order to eliminate any change in humidity...

The reason i am asking is the readings are going up and down. any where from 70-80 %... i followed Gensings instructions and pics of a slury. Any1 else have this problem

 

[Ginseng]

I would try doing it in a jar. If you're just using a plain ziploc bag, I don't feel the barrier is sufficient to allow things to stabilize well. If you must use a ziploc, I'd use at least a single freezer bag as those are quite a bit thicker.

Is the zipper sealed?

Wilkey

 

[Anthony]

Is the bag near a window? Perhaps sunlight may be causing temperature fluctuations enough to have an effect over the 12hrs it's been sitting there.

 

[mysterea]

I had a similar experience when I was salt testing my new batch of meters, and it seemed to happen because I had put too much water in my salt.
As time went on the salt would shed some water and create a small puddle. eventually I 'blotted dry' the surface of the salt and let it sit for about 24 hours, that worked like a champ.
Is it possible that you could blot it 'dry' and see if that helps?

 

[BlindedByScience]

I had the same experience you're having until I started "double bagging" the test; one bag inside the other. As Wilkey suggests, a mason jar would work great as well.

Good luck - B.B.S.

 

[mmburtch]

isn't this test done in order to check how close it is to 70%?

Salt test reading should be 75%

 

[MillhizzelPB]

ahhhhh hhhhaaaa... Thanks guys i will try double bagging it... that makes sense. Wilkey, the bag is sealed... i am not that much of a NEWB :laugh:

 

[Ginseng]

isn't this test done in order to check how close it is to 70%?

Salt test reading should be 75%

Yes, that's right.

Rob, a saturated salt slurry will not shed water in the sense of releasing liquid unless the surrounding conditions change such that the slurry is now over-saturated. For example, if the temperature drops tens of degrees. Or, if the slurry is absorbing water from the environment (which must be greater than 75% RH).

It's possible that in a slurry that is starved of water, the salt does not entirely dissolve right away. When water gets to all the salt grains and begins solvation, this may result in the delayed appearance of a liquid phase. In this case, it would not be pure water that "weeps" from the slurry, but rather the appearance of the liquid phase of the saturated salt pile.

I think the latter explanation is the more likely case here, and generally.

That's why I always establish a clear layer of liquid. This promotes solvation and buffers the equilibrium between the undissolved salt, the saturated salt solution, and the atmosphere.

Wilkey

 

[Allofus123]

After double bagging it or placing it in a jar leave it alone and stop watching it. The fact that it changes within the 12 hour period is nothing out of the ordinary...... especially with some digital hygrometers. Give it 24 hours and it needs to be left undisturbed in a constant temperture part of the house.

Did you say this was a digital hygrometer?