0.5 mEq/mL acid solution made from 20% HCl

[Silver_Is_Money]

20% HCl is readily available at places like Lowes and TSC (Tractor Supply Co.).

I've calculated that (provided that the commercial HCl is truly 20%) a nominal 82.9 mL of 20% HCl solution made up to 1,000 mL with distilled water will give me 1L of an HCl solution with 0.5 mEq/mL

Does 82.9 mL per Liter sound right to you, or am I way off base here?

 

[Silver_Is_Money]

In case anyone is wondering, this solution would not be used on anything to be consumed. It would only be used to titrate Worts derived from base malts which can effectively be considered to be basic with respect to typical mash pH targets.

 

[Vale71]

That appears to be correct to the second decimal place.

 

[Silver_Is_Money]

That appears to be correct to the second decimal place.

I was just beginning to think I was perhaps off by a factor of 1,000 somehow, such that perhaps 0.0829 mL of 20% HCl was the correct answer for making a 1L solution of 0.5 mEq/mL acid.

20% HCl is listed as having the following characteristics:

Density = 1.098 g./mL
Normality = 6.023

 

[Vale71]

82.9 X 1.098 = 91.0242

91.0242 X 0.2 = 18.20484

18.20484 / 36.46094 = 0.49929705597277524934902939968086‬ Eq/l or mEq/ml

I'd say you're pretty close.

 

[Silver_Is_Money]

82.9 X 1.098 = 91.0242

91.0242 X 0.2 = 18.20484

18.20484 / 36.46094 = 0.49929705597277524934902939968086‬ Eq/l or mEq/l

I'd say you're pretty close.

Thank you! Sanity is restored. My dad always told me: "Son, don't ever get old!"

 

[Silver_Is_Money]

My new line of reasoning is that the acidity of the various of malts and unmalted grains is not (as for all current mash pH assistant software) a function or measure of how many Kg of these malts/grains one starts out with in any given all grain beer recipe, but rather is much better correlated to the density of the Wort that one ends up with in conjunction with the percentage of the Wort density (SG) that is found to be attributable to each individual grist component. Unless I'm so far behind that I've deluded myself into thinking I'm in the lead*, I believe I'm comming at Mash pH adjustment at the ground floor level here. I wish I was young again. Much to ponder here.

*Picture here a race car that is about to be lapped, wherein the driver about to be lapped is so far behind that if he wasn't paying attention to details and the history of the race as it was unfolding all along he could potentially at this juncture of nearly being lapped actually be confounded/confused/deluded into thinking himself in the lead.

 

[z-bob]

Are you sure it's 20%? I thought muriatic acid was typically 31.45%

 

[Silver_Is_Money]

Are you sure it's 20%? I thought muriatic acid was typically 31.45%

Concentrated HCl at essentially full saturation is ~37.2% (and can range from 37% to 38%)
Some technical grade hovers at around 32% (Example: Duda Diesel)
TSC and Loews specify 20% for some odd reason

 

[Silver_Is_Money]

For titrating the Worts of acidic malts/grains (again, if I'm looking at this correctly):

4 g. NaOH crystal made up to 1L with distilled = 0.10 mEq/mL
20 g. NaOH crystal made up to 1L with distilled = 0.50 mEq/mL
40 g. NaOH crystal made up to 1L with distilled = 1.00 mEq/mL

And to round out the acid titrants made from 20% HCl I get:

16.6 mL of 20% HCl made up to 1L with distilled = 0.10 mEq/mL
82.9 mL of 20% HCl made up to 1L with distilled = 0.50 mEq/mL
165.8 mL of 20% HCl made up to 1L with distilled = 1.00 mEq/mL

One snag will be the mashing of non-diastatic malts and grains. Of which there are a boat load.

 

[Silver_Is_Money]

It makes no difference as to what the initial percent concentration of the HCl is. All that matters is that you know both the percent concentration and the density.

mL's to be made up to 1L = (MW * Targeted mEq/mL)/(Density * % Concentration * Valance)

(Where MW = Molecular Weight)

Example: Lets target making 1 Liter of a 0.1 mEq/mL solution and use 37.2% HCl, diluting some quantity of it to 1 Liter with distilled water:

mL of 37.2% HCl = (36.4094 * 0.10)/(1.19*0.372*1)
mL of 37.2% HCl = 8.22

Therefore: If 8.22 mL of 37.2% HCl are made up to 1 Liter using distilled water the resulting 1 Liter solution has a strength of 0.1 mEq/mL

The critical rule is to add acid to water, so start with 500 mL of room temperature distilled water in a 1L (1,000 mL) flask. Add to this the 8.22 mL of concentrated HCl. Stir. Then make this mixture the rest of the way up to 1L by adding additional distilled water and stirring.

 

[Silver_Is_Money]

The general goal as I'm envisioning it is to replace mEq/Kg valuations for malts and grains with mEq@Wort_Density/Liter_Of_Wort valuations. Does this seem doable?

 

[Silver_Is_Money]

If you already know the mEq/mL of an acid or base and you want to move it to a lower mEq/mL via dilution with distilled water, this simple formula works:

mEq/mL1(Volume1) = mEq/mL2(Volume2)

If we apply this formula to the 37.2% HCl example above, and accept 12.18 mEq/mL for the 37.2% HCl we get:

(12.18*8.22)/0.1 = Volume2 = 1001.2 mL

Where 1001.2 mL is right close to the 1,000 mL volume to which the 8.22 mL must be made up, and any small difference is merely due to rounding error, and/or error in the presumption of 12.18 as the initial mEq/mL value.