A proposal whereby to verify or repudiate Kolbach's contention that 3.5 mEq's of Ca++ will reduce 1 mEq of alkalinity

[Silver_Is_Money]

Awhile back I noticed this equivalence relationship, which I present here as copied from the post I made awhile ago revealing it.

MW of Ca(OH)2 = 74.09268, so therefore the Eq Wt of Ca(OH)2 = 37.0463
MW of NaHCO3 = 84.0066, so its Eq weight is also 84.0066

37.0463/84.0066 = 0.440993

If there was no calcium ion downward impact upon mash pH shift, then 0.440993 grams of Ca(OH)2 would be the alkalinity and thereby pH raising equivalent of 1 gram of baking soda.

But for the use of Ca(OH)2 every mEq of added OH- also introduces 1 mEq of Ca++ into the mash

Per Kolbach it takes 3.5 mEq's of Ca++ to reduce 1 mEq of alkalinity.

1/3.5 = 0.2857 mEq of alkalinity reduction due to the calcium ion present within Ca(OH)2.

As a consequence of this, 0.2857 x initial Wt of Ca(OH)2 is required (in addition to the initial Ca(OH)2 addition) whereby to counter the impact of the added calcium.

But then this corrective addition brings along with it 0.2857/3.5 = 0.08163 mEq's of alkalinity reduction, etc..., etc..., so on and so on, ad-infinitum.

This infinite chain can be represented mathematically as 1 + 0.2857 + 0.2857^2 + 0.2857^3 + 0.2857^4, + 0.2857^5 ... etc..., whereby 1 is the initial need for 0.440993 x baking soda, and the rest are needed additions of OH- mEq's to counter the calcium that comes with it each time, adding to infinity.

Solving for this gives:

1 + 0.2857 + 0.2857^2 + 0.2857^3 + 0.2857^4 + 0.2857^5 ... = ~1.39921 (plus a minuscule scooch more to account for the infinity part left off here)

So ultimately, to counter the pH reduction of its own calcium, and to bring equivalence to baking sodas pH rise in the mash, one must add:

0.440993 x 1.39921 = 0.617 grams of Ca(OH)2 for every calculated 1 gram of baking soda required

Now for the proposed test of Kolbach:

If one adds a certain weight of Baking Soda to a mash and observes the upward pH shift induced upon the grist thereby, and then performs an exact duplicate of this grist mash adding instead Calcium Hydroxide at a weight of 0.617 x Baking Soda, and the resulting mash pH is higher than that for the baking soda mash, then the Kolbach contention of 3.5 mEq of added calcium being the opposite sign equivalent of 1 mEq of Alkalinity (as CaCO3) within the mash is repudiated.

A total repudiation would require that instead of 0.617 x Baking Soda grams, 0.441 x Baking Soda would be required to mash at the same pH for both duplicate grists. But we know that to some extent calcium does indeed lower mash pH, and we know that there is calcium within Ca(OH)2, so the real answer must lie between the two extremes of 0.441X and 0.617X, whereby if it is 0.617X then Kolbach is vindicated, and if it is less than 0.617X, then Kolbach is repudiated and a new factor for calcium other than 3.5 will emerge from the testing.

A side consequence of any such repudiation of Kolbach's 3.5 factor for calcium would be the realization that RA (Residual Alkalinity) as quantified in relation to 3.5 is incorrect.

 

[Silver_Is_Money]

The speculation here (as bolstered by AJ deLange, and other of my posts addressing this subject, which reference recent research) is that 3.5 will likely prove to be too low a divisor, and that a divisor in the range of 7 to 10 may prove to be more correct. This would indicate that the mash pH reduction witnessed for calcium additions is not as markedly great within specifically the confines of the mash as has been generally presumed for many decades. The only thing new that this thread brings to the table is a different and new scientific approach whereby to measure the deviation from Kolbach's 3.5 divisor factor (if any). This approach has the added benefit of honing in on a better means of assessing the pH raising potential for Ca(OH)2.