Chemists Help - Trouble Making 3M KCL Solution

Renfro

Well-Known Member
Here is a link to the thread I posted with info I found on making your own 3M KCL pH probe storage solution.


I did check several sources and the recipe appears to be correct.


I added the precisely measured 22.37 grams of KCLto 100 mL of 2 PPM RO water and I put it on my stirring plate with a lid to prevent evaporation. Set it to stirring at good speed. I checked it the next day after about 10 hours of stirring and it's a saturated solution with some salt that failed to dissolve. For shits and giggles I approximately doubled the H2O in the jar and it managed to dissolve it all but the solution is very cloudy unlike the stuff from Bluelab. Definitely not gonna mess up a pH probe with that chowder looking crap. lol

The 100 mL of H2O should take like 33 grams of KCL right?

Scale calibration verified. H2O was measured with a 100 mL graduated cylinder.

Do you all think it's bad KCL or did having 2 PPM of shit in my water really fuck things up that much? Or am I missing something due to my density? :wall:
 

Dr. Who

Well-Known Member
Here is a link to the thread I posted with info I found on making your own 3M KCL pH probe storage solution.


I did check several sources and the recipe appears to be correct.


I added the precisely measured 22.37 grams of KCLto 100 mL of 2 PPM RO water and I put it on my stirring plate with a lid to prevent evaporation. Set it to stirring at good speed. I checked it the next day after about 10 hours of stirring and it's a saturated solution with some salt that failed to dissolve. For shits and giggles I approximately doubled the H2O in the jar and it managed to dissolve it all but the solution is very cloudy unlike the stuff from Bluelab. Definitely not gonna mess up a pH probe with that chowder looking crap. lol

The 100 mL of H2O should take like 33 grams of KCL right?

Scale calibration verified. H2O was measured with a 100 mL graduated cylinder.

Do you all think it's bad KCL or did having 2 PPM of shit in my water really fuck things up that much? Or am I missing something due to my density? :wall:

Your issue is with Alpha Chemical as the source.
Their chem's tend to have issues dissolving, and being cloudy...

I use nothing but Greenway Biotech Chemicals. These are vastly superior for all gardening needs. They are made to easily dissolve in RO or filtered waters! They also have a superior value by volume rates. This is where your 22.37 grams comes into play....

Lastly, you really might want to use weight to measure that 1000 ml of water!~

1000.00 grams
35.27 ounces

GREENWAY BIOTECK KCl source

Good luck Renfro!
 

Renfro

Well-Known Member
Your issue is with Alpha Chemical as the source.
Their chem's tend to have issues dissolving, and being cloudy...

I use nothing but Greenway Biotech Chemicals. These are vastly superior for all gardening needs. They are made to easily dissolve in RO or filtered waters! They also have a superior value by volume rates. This is where your 22.37 grams comes into play....

Lastly, you really might want to use weight to measure that 1000 ml of water!~

1000.00 grams
35.27 ounces

GREENWAY BIOTECK KCl source

Good luck Renfro!
100 mL
 

OGBudz

Well-Known Member
Question, when should i be using kcl solution? Do i only use it if my meter isn't gonna be in use for more than a month or something?
 

Dr. Who

Well-Known Member
Question, when should i be using kcl solution? Do i only use it if my meter isn't gonna be in use for more than a month or something?
ALL THE TIME!

Multi meter pens -Especially those expensive Ph - EC - PPM ones are notorious for needing the probes to be replaced. Probes for those are expensive!

I strongly suggest those of you shopping.....DON'T get one of those!

ALWAYS store pH pens in some sort of storage solution.
 

Renfro

Well-Known Member
Question, when should i be using kcl solution? Do i only use it if my meter isn't gonna be in use for more than a month or something?
Your pH probe has a KCL reference solution in the probe tip. When thats depleted the probe is done for. Storing the probe in the KCL solution preserves the probes life. Always store it in the proper KCL solution. Most probes have a provision to put a little KCL solution in the probe cap.
 

Renfro

Well-Known Member
Multi meter pens -Especially those expensive Ph - EC - PPM ones are notorious for needing the probes to be replaced.
I agree. I used to run Hanna HI98129 pens back in the day (PPM and pH). The pH probe was replaceable for about $60 and a new pen for about $120. The first several years I used those they would last about a year. Then suddenly they wouldn't even last a few weeks. I think they were on the shelf way too long or something. So I quit using them. Those were the only multi function pens I ever had luck with but alas no more.
 

OGBudz

Well-Known Member
Thanks for the info guys, Would've been nice for the manufacturer to include that info...all the manual says is "if storing long term use KCL solution"
 

Renfro

Well-Known Member
@Renfro Can you try the same thing in PH 4 buffer solution? Just a hunch
You mean storing the probe or making your own pH 4 calibration solution?

If storage, no it's the wrong chemical.

If making your own pH 4.0 solution you would need to test it to be sure it's at the proper pH and I would not be sure how stable it is as I don't know if they add anything to stabilize when making pH buffers.
 

Aqua Man

Well-Known Member
@Renfro I was looking all this up a week or 2 ago. Here is something I found.

If you wish to prepare your own storage solution, you can do so by adding 10g of solid potassium chloride (KCl) to 100 mL of a buffer pH 4 solution. It is also a good idea to add some buffer preservative (add 3 drops preservative/100 mLs solution).
If you do not have pH 4 buffer solution, Add 2.0 mL of 0.1 M HCl to 1000 mL of 0.1 M potassium hydrogen phthalate.
 

Aqua Man

Well-Known Member
You mean storing the probe or making your own pH 4 calibration solution?

If storage, no it's the wrong chemical.

If making your own pH 4.0 solution you would need to test it to be sure it's at the proper pH and I would not be sure how stable it is as I don't know if they add anything to stabilize when making pH buffers.
I removed and reposted. not done it yet but I have the stuff here now
 

Renfro

Well-Known Member
@Renfro I was looking all this up a week or 2 ago. Here is something I found.

If you wish to prepare your own storage solution, you can do so by adding 10g of solid potassium chloride (KCl) to 100 mL of a buffer pH 4 solution. It is also a good idea to add some buffer preservative (add 3 drops preservative/100 mLs solution).
If you do not have pH 4 buffer solution, Add 2.0 mL of 0.1 M HCl to 1000 mL of 0.1 M potassium hydrogen phthalate.
Having to use the buffer makes the whole thing pointless. I want to make the KCL cheap lol.
 

Aqua Man

Well-Known Member
I even tried drying the KCL powder in the microwave lol. I think Dr. Who is on to something though, I ordered a bag of the Greenway stuff to try.
Yeah i did the exact same shit... Im not getting complete dissolution. It below the saturation point so I think as you say Mr.Who is probably right... Let me know how it works out for ya... I'm going to see what i can get for max dissolution on this and probably just use that. It better than just buffer solution.
 

Aqua Man

Well-Known Member
I even tried drying the KCL powder in the microwave lol. I think Dr. Who is on to something though, I ordered a bag of the Greenway stuff to try.
Hey man been doing a bit more readin on this and apparently it seems anything between 1M and 3M is acceptable for a storage solution. I'm wondering if most sell 3-4 M because of the difficulties to make? If you have any insight or came across anything that I didn't that may indicate a lower 1-2M solution would not be adequate would you be so kind as to share? Just thought i would drop this in here for food for thought. Interested to see how the other source works out.
 

Renfro

Well-Known Member
TBH all I know is what the Apera support people told me. That is, they use 3M KCL. Blue Lab does as well. I am not familiar with any reason one couldn't use the weaker solution except for perhaps reduced effectiveness. It should definitely preferable to tap water or no storage solution lol.
 
Top