Ro or tap

[PeeBee]

… That aside: Tried my refractometer on my SG1.072 CaCl2 solution and got 15.2. That was done a bit slap dash so I'll give it another go later.

Very carefully repeated the refractometer reading, twice. I've known from use that the glass slide and cover need to be very clean. But both times I got little change, both 14.9degreesBRIX (down 0.03 from first 'slap-dash' reading).

Also repeated weighing the solution: Glass measuring cylinder 40.53g empty, 67.36g with 25ml of solution. Therefore 25ml weighs in at 26.73g., therefore SG of solution = 1.069 (26.73/25). The review ends up with lower density than before! The solution is about 7.7% CaCl2 (down from 8%).

100g calibration weight coming in at 100.48g.

Something is wrong?

[Silver_Is_Money]

Everything points to the SG being near 1.081, except your scale method.

S.G. = Density/0.9976

That brings your calculated S.G. up a tad, but not enough.

I'd wager that not 1 in one hundred know that S.G. is not exactly the same thing as g/CC (density).

[Silver_Is_Money]

100.48/100 x 26.73 = 26.8583 g.

26.8583/25 = 1.07433 density

1.07433/0.9976 = 1.07692 S.G.

Closer.

[Silver_Is_Money]

14.9 Brix = 1.08033 S.G.

Try hitting it with your hydrometer again.

[PeeBee]

14.9 Brix = 1.08033 S.G.

Try hitting it with your hydrometer again.

Thanks. I hadn't suspected my refractometer had gone out of calibration. But all the information I can find puts 14.9 BRIX as SG 1.060-61? So the refractometer can join the hydrometer in the bin. Actually, I did give the hydrometer another chance, but it reads 1.082 as before. So the only reliable reading is by weight and volume (26.73g for 25ml). Pyknometers certainly look the best bet for replacing the defective instruments (and a very swish name for a bottle with a hole in the stopper).

So, gravity of my CaCl2 solution stands at 1.069 (g/ml).

[Silver_Is_Money]

ASTM and ISO both agree that specific gravity = density/0.9976

https://www.intertek.com/polymers/testl ... astm-d792/

Density, kg/m3 = (specific gravity) x (997.6

[PeeBee]

"Intertek"! My partner works for them. I had to get her to remind me those bottles with a hole in the stopper are called "pyknometers".

<EDIT: The spelling is debatable, but you also see the spelling "pycnometer", but hard "c" please.>

[Silver_Is_Money]

14.9 Brix = 1.08033 S.G.

Try hitting it with your hydrometer again.

Thanks. I hadn't suspected my refractometer had gone out of calibration. But all the information I can find puts 14.9 BRIX as SG 1.060-61?

14.9 BRIX = 1.0607 S.G. is correct for sugar water, but certainly not for calcium chloride water. Calcium chloride has a different refractive index from that of sugar.

[PeeBee]

Of course, sorry.

[Silver_Is_Money]

You could take a Brix scaled refractometer reading of it:

Grams of CaCl2 per Liter of solution = 5.9392*Bx + 0.050098*Bx^2 -0.00018856*Bx^3 + 4.7399e-06*Bx^4

(where Bx = Brix)

I just discovered an easy way to drop this formula into a spreadsheet without ever needing to touch the formula itself.

1) Copy the entire formula as seen above from the "=" sign to the right, including the "=" sign. Highlight and hit "Ctrl-C", or just right click and select copy.
2) Enter a spreadsheet, and click on a random cell. I randomly clicked on F10,
3) Press 'Ctrl-V' and select "Automatic" to paste the formula into the cell (in this case F10). In my case this merely required hitting "Enter" as I recall. You will be greeted with an error within the cell that in LibreOffice is "#NAME".
4) Now click on the cell to the left of where you pasted the formula and see "#NAME". In my case it was E10.
5) Now look to the upper right of the spreadsheet and find where there is a box in which "E10" (or whatever cell your cursor is in) is visible. With your cursor highlight "E10" (or the actual cell name) in this box, and while it is still highlighted type "Bx" (capital B and lower case x) over it and hit "Enter".
6) You should now see where the F10 (or whatever) original cell with the formula pasted into it reads "0" (zero), and the 'E10' cell is now no longer E10, as you have renamed it to cell Bx.
7) In newly renamed cell Bx enter any BRIX value, and in the cell with the formula you will now see the grams of anhydrous calcium chloride in 1 liter of your solution.

[PeeBee]

Right! I'll switch to home-brewer mode and use what's in the kitchen. Kitchen scales, 1 gram resolution but reads up to 2Kg. Plastic measuring cylinder (once for hydrometer) 250ml mark (fairly accurate, weighing-scales confirm 250ml water weighs 250g). Using these, bottle of prepared CaCl2 solution contains 465ml and weighs 505 grams (solution only). So solution is 1.086g/ml, and if we really want to get farty, 1.086 / 0.9976, SG = 1.089. That'll do, and by using kitchen implements, not cheapo pseudo-laboratory kit from China. So I've a 10% (9.8 or 9.9%, does it really matter) CaCl2 solution (see graph earlier).

The point of all this is I have a CaCl2 solution I (personally) can rely on, instead of a solid that contains a unknown random quantity of water. Morel of all this: Create a litre (or 1/2 litre) of solution and weigh the entire quantity (to the nearest gram) and measure quantity of solution as best you can (to nearest ml). Weight divided by volume (divide by 0.9976 if you really must) is SG. And don't bring a refractometer anywhere near it unless you are trying for a brain aneurysm.


(Now how do I get back to other side of this "looking glass". Does that "Guypettigrew" know?)

<EDIT: Whoops, bit of mixing up divide and multiply with that "correction" factor. Fixed! >

[PeeBee]

… I just discovered an easy way to drop this formula into a spreadsheet without ever needing to touch the formula itself. …

That worked. And without my head going numb with all those numbers:

Capture.JPG (10.5 KiB) Viewed 9351 times

(This in Excel). 99.2262g anhydrous CaCl2 per litre (actually used 66.25g of supposedly "dihydrate" form in 0.5 litres). I wasn't too careful with volume (tad short) and "dihydrate" is supposed to be a mix of other hydrated forms, hence the surprising "99%" tag? The flakes were kept in a zip-locked bag, but are 4 years old. But I'm still surprised the CaCl2 isn't wildly out.

All this mucking about to get a useable CaCl2 solution has got to be good reason not to use CaCl2 if possible. There's common salt (NaCl) and Magnesium Chloride (can MME include that?), even Potassium Chloride is easily available.

[Jocky]

All this mucking about to get a useable CaCl2 solution has got to be good reason not to use CaCl2 if possible. There's common salt (NaCl) and Magnesium Chloride (can MME include that?), even Potassium Chloride is easily available.

Surely your calcium chloride was 'usable' for brewing levels of accuracy in the first place? Yes, you may end up under-dosing it in some cases, but I doubt that would be to a degree that is going to make a noticeable difference in your final beer... unlike the levels of magnesium/sodium you might add if using your alternatives.

The brewing process adds an awful more chloride to your finished beer than you would usually add in any case (something in the range of 150-250ppm from the evidence I've seen).

[PeeBee]

… Surely your calcium chloride was 'usable' for brewing levels of accuracy in the first place? Yes, you may end up under-dosing it in some cases, but I doubt that would be to a degree that is going to make a noticeable difference in your final beer... unlike the levels of magnesium/sodium you might add if using your alternatives.

The brewing process adds an awful more chloride to your finished beer than you would usually add in any case (something in the range of 150-250ppm from the evidence I've seen).

If my solid CaCl2 is proving "usable", that's only because of the mucking about in the last few days "analysing" it. Was it "useable" last year? Will it be "usable" next year? A solution should be.

I'm sure it's solid CaCl2 that's responsible for trashing my cheapo weighing scales (I'm on my third set).

I benefit from the extra magnesium/sodium using the alternative salts, many won't? That is why I included Potassium Chloride. All the chloride salts are easily obtainable, the Magnesium Chloride (Hexahydrate) is an "in" health fad at the moment, isolated from the Dead Sea. I'm pretty sure MgCl2 doesn't suffer from the hygroscopicity of CaCl2. I may get put right?

And finally the "why bother" argument. I'm definitely not going there!

[PeeBee]

Least we forget (!): This is "Brown Beer's" thread, and I have together the ingredients to copy his intended beer:

And the water calculations by MME:

I'll try to put up an illustration of water calculations using MME for "Brown Beer's" supply. That should be a shock after this extensive hi-jacking of his thread!

And yes, I am using a "Grainfather" for this exercise. And I am aware this is a BIAB forum. Explanation following …