Make your own Calcium Hydroxide? Yeah, right...

[evoo4u]

Or better - do 2 identical beers. One with chalk, one with lime.

Would you expect one to be much different from the other? I never was any good at chemistry, but they're both adding calcium (good for yeast, they tell me).

And the rule of thumb - chloride = maltier, and sulphate = hoppier, wouldn't apply here would it?

 

[manticle]

Talking hydroxide vs carbonate and effect on pH rise.

 

[Lyrebird_Cycles]

No, I would expect them to be very similar once the different MWs of the two compounds are taken into account (CaCO3 is ~100 , Ca(OH)2 is ~75 so the ratio is ~4:3)

The result above gives a very different ratio. I suspect that the chalk didn't have enough time to react, so some of the effect you ascribe to the hydroxide is actually due to a delayed reaction with the chalk.

This is why I'd like to see it done with the order reversed.

Neither carbonate nor hydroxide have any effect on remnant anions at the pH of beer (apart form the effect on pH itself).

 

[wynnum1]

Not sure how you would make calcium hydroxide in a house oven.
calcium oxide is what is made from calcium carbonate
calcium sulfate which they say may be blackboard chalk would be a bad idea.
http://www.wikihow.com/Make-Quicklime

 

[Lyrebird_Cycles]

By adding water.

CaO + H20 -> Ca(OH)2

Nanny warning: reaction is vigorous and exothermic.

Don't do this in you SO's favourite casserole dish.

 

[evoo4u]

Not sure how you would make calcium hydroxide in a house oven.

I used the reaction of a Caustic Soda solution with a Calcium Chloride solution at ambient temperature. Calcium Hydroxide precipitates out. Drain off the salt water, and dehydrate the Ca(OH)2. Leave it in the sun long enough, or a dehydrator, or in a very low oven which does the job faster.

When it's dried, pummel it into a powder with a mortar and pestle. High temperatures were not required.

 

[wynnum1]

I used the reaction of a Caustic Soda solution with a Calcium Chloride solution at ambient temperature. Calcium Hydroxide precipitates out. Drain off the salt water, and dehydrate the Ca(OH)2. Leave it in the sun long enough, or a dehydrator, or in a very low oven which does the job faster.

When it's dried, pummel it into a powder with a mortar and pestle. High temperatures were not required.

There is going to be some salt left with the Calcium Hydroxide after its dried .

 

[MHB]

Yes but the solubility of Calcium Hydroxide is only about 1.7g/L, NaCl is over 350g/L so it would be quite easy to rinse the precipitate a couple of times the salt would be dissolved and the loss of your hydroxide would be minimal.
Mark

 

[evoo4u]

That's what I did.