Chemistry question

Originally posted by robbie carrobie
does bleach really act as a sanitiser or not?

if you are brewing up a storm when is it party time oh wise one.

Originally posted by robbie carrobie
does bleach really act as a sanitiser or not?

Bleach acts as sanitizer as was already stated.
The way it reacts is to set free oxygen, oxidising bacteria, fungi,...
Bleach is not toxic in that, but if you drank bleach your mucosa would be oxidised which is very painful, so you can't really drink bleach in toxic doses until it is administered by force.
You would imidiately nortice a funny taste in your beer if bleach would have been left in it.

Originally posted by robbie carrobie
yes you can use steam. Kettles are converted stainless steel beer kegs with heating elements fitted. My small one has two elements that I ripped from two smaller kettles used for making tea and the larger one, elements ripped from a washing machine. They hold roughly about 60-80 litres. Commercial ones are much, much, much bigger. Personally I fav ...[text shortened]... gians are famous for that kind of thing although others prefer a much greater degree of control.

If you can use steam, that would be the way to go. I would use distilled water since you are making a beer that can be altered in taste by contaminants in city water. You should use distilled water for all your brewing.

Originally posted by Ponderable
Bleach acts as sanitizer as was already stated.
The way it reacts is to set free oxygen, oxidising bacteria, fungi,...
Bleach is not toxic in that, but if you drank bleach your mucosa would be oxidised which is very painful, so you can't really drink bleach in toxic doses until it is administered by force.
You would imidiately nortice a funny taste in your beer if bleach would have been left in it.

thanks i am very reticent about using bleach, i much prefer sanitising tablets that are used for babies bottles. I think they are chlorine based.

Originally posted by sonhouse
If you can use steam, that would be the way to go. I would use distilled water since you are making a beer that can be altered in taste by contaminants in city water. You should use distilled water for all your brewing.

Water is not a problem in Glasgow, distilled water may also not contain many of the nutrients that yeast needs to reproduce. The rule is that if your water is fine to drink, its fine to make beer. Some style of beer in fact requires hard water by adding things like gypsum. Personally I cannot be bothered with that jive and prefer a style of beer made with soft water.

Originally posted by robbie carrobie
Water is not a problem in Glasgow, distilled water may also not contain many of the nutrients that yeast needs to reproduce. The rule is that if your water is fine to drink, its fine to make beer. Some style of beer in fact requires hard water by adding things like gypsum. Personally I cannot be bothered with that jive and prefer a style of beer made with soft water.

Distilled water has nothing in it but H2O, O2- and H+ in it, nothing more.
If it has anything more in it it is not distilled water by definition.

However, if you have distilled water and something more in it, thus not being distilled anymore, then it can have nutrients in it that yeast needs to reproduced. But please, then don't call it distilled water.

Originally posted by FabianFnas
Distilled water has nothing in it but H2O, O2- and H+ in it, nothing more.
If it has anything more in it it is not distilled water by definition.

However, if you have distilled water and something more in it, thus not being distilled anymore, then it can have nutrients in it that yeast needs to reproduced. But please, then don't call it distilled water.

There is another level of water beyond distilled. That is called DI water.

We measure the resistivity of our water here because we use all three versions in our plant, city water, which comes in about 2500 Ohm/square cm and distilled water which comes in at about 200,000 ohms/square and then DI water which theoretically has nothing but H2O molecules and that tops out at 18 Megohms per square cm. Our DI water here is not quite that good, topping out at about 5 megohms per square, significantly better than distilled but not the absolute best, good enough, however, to rinse off our product after certain processes. It is also interesting that DI water, in order to stay DI water, has to recirculate through the DI water system. We are going through that problem as we speak here at Gulton. We are preparing to add a system that recirculates the DI water so there are no dead ends, like the ends of piping going to a faucet or some such where it goes for a day or more without flow. It turns out that ruins the DI-ness where various ions get into the water from the piping, even though we use PVC and not metal. Metal is the death of DI water, since DI water is so polar the molecules attacks metals and then, oops, no more DI water.

Originally posted by sonhouse
There is another level of water beyond distilled. That is called DI water.

We measure the resistivity of our water here because we use all three versions in our plant, city water, which comes in about 2500 Ohm/square cm and distilled water which comes in at about 200,000 ohms/square and then DI water which theoretically has nothing but H2O molecules and ...[text shortened]... water, since DI water is so polar the molecules attacks metals and then, oops, no more DI water.

You say that DI water is just a hypothetical kind of water with theoretical properties? That DI water, if existed, become pure distilled water, in a jiffy?

BTW - what stands DI for?

Originally posted by FabianFnas
You say that DI water is just a hypothetical kind of water with theoretical properties? That DI water, if existed, become pure distilled water, in a jiffy?

BTW - what stands DI for?

It's not hypothetical. DI stands for "De-Ionized". So you remove as many ions as possible from regular water, city or distilled and when you have nothing but H2O molecules, the resulting resistance in terms of ohms/square cm is around 18 megohms or in the inverse notations of Siemen's which is about 50 Nanosiemens which is the way people talk about DI water, using Siemen units. The result is the fact that H2O is polarized due to the molecular arrangement of the H and O atoms, a bit like the Mickey Mouse ears we see in cartoons, the Oxygen's not at 180 degrees apart like you would think but at 105 degrees apart, within 15 degrees of a right angle. So that puts positives on one side and negatives on the other, a polar molecule.

That allows this ultra pure water to attack metals especially and anything else the polar nature of the molecule can attack. Like PVC plastic, it will grab on to stuff like the plastisizer, like Pthalates and such. That is why A) you don't use metal piping or fittings if you want to keep them in one piece, you have to use stuff like teflon instead which pretty much ignores the polar aspect of DI water. And for the best results, that is to say, to keep the resistance at 18 megs or 50 nanosiemens, you need to recirculate that water to buff it back up to 18. You also have to kill bacteria and algae in such a system, so another unit is required, an ultraviolet column that kills all those bugs and allows them to collect in the filtering system. Otherwise, living bugs will cause biofilms to build up inside the system.

One of our problems with our minimalist system is just that, algae build up inside our plastic piping, some of which is transparent and the buildup is obvious.

That is why we are adding units like recirculators and ultraviolet columns to keep the DI water up to snuff and to minimize algae.

Originally posted by sonhouse
It's not hypothetical. DI stands for "De-Ionized". So you remove as many ions as possible from regular water, city or distilled and when you have nothing but H2O molecules, the resulting resistance in terms of ohms/square cm is around 18 megohms or in the inverse notations of Siemen's which is about 50 Nanosiemens which is the way people talk about DI water ...[text shortened]... ke recirculators and ultraviolet columns to keep the DI water up to snuff and to minimize algae.

Distilled water is H2O, and O2- and H+. If you remove all the ions it doesn't take long before H2O splits into new O2- and H+ until equilibrium occurs. Microseconds? So in real world water with only H2O doesn't exist for long.

However, theoretically, we know the properties of pure H2O without ions. But only in theory. Is it even measurable in a lab? I don't think so.

How do you practically eliminate the ions without creating new ones in its absense?

But if you know more than I do, then I will naturally fold.

Originally posted by FabianFnas
Distilled water is H2O, and O2- and H+. If you remove all the ions it doesn't take long before H2O splits into new O2- and H+ until equilibrium occurs. Microseconds? So in real world water with only H2O doesn't exist for long.

However, theoretically, we know the properties of pure H2O without ions. But only in theory. Is it even measurable in a lab? I ...[text shortened]... creating new ones in its absense?

But if you know more than I do, then I will naturally fold.

Trust me, it's not theoretical, Deionized water exists and stays around for quite a while. I myself have measured the resistance of all three types, city water, which comes out around 3 Kohms, distilled, comes in at around 200,000 ohms or 5 microsiemens and perfect DI water, 18 megs and change.

It's true, DI water does not stay DI forever, it may do as you say, but not in total in milliseconds. In city water there are many kinds of pollutants and the water molecules will latch on to them so the polar nature of the molecule is neutralized.

But when all the pollutants and ions are removed, they become like mice traps and will take out metal atoms bit by bit till again the water molecules are in equilibrium with respect to the polar nature of water.

I know for a fact this re-ionization does not occur at the rate you indicate because I have a measuring device, similar to an ohm meter, that accurately says what the ohm/square cm reading is. If DI water sits around for a few hours it will start to lower its resistance, indicating an increase in ions, giving more conductivity to the water. But it does not happen in milliseconds.

It still happens fast enough you need to recirculate the water and run it through the ionization removal technologies of which there are several, like electric field removal systems, ion exchange resins and so forth.

Here is a bit about DI water:

http://puretecwater.com/what-is-deionized-water.html

And this:

http://www.reddit.com/r/askscience/comments/1bwbuu/how_does_deionized_water_stay_deionized/

Note the last sentence, DI water takes hours for a molecule to re-ionize so the major contributor to the re-ionization is in fact the material used in the piping.

Major systems use only teflon piping which interacts with water the least of all the plastics. We are cheap here, using PVC pipes which contribute to re-ionization at a much faster rate than teflon.

Originally posted by sonhouse
Trust me, it's not theoretical, Deionized water exists and stays around for quite a while. I myself have measured the resistance of all three types, city water, which comes out around 3 Kohms, distilled, comes in at around 200,000 ohms or 5 microsiemens and perfect DI water, 18 megs and change.

It's true, DI water does not stay DI forever, it may do as y ...[text shortened]... cheap here, using PVC pipes which contribute to re-ionization at a much faster rate than teflon.

I learn something new every day. I thank you for the today's lesson 🙂

Originally posted by FabianFnas
I learn something new every day. I thank you for the today's lesson 🙂

Your Velcome🙂

Ok, i have another chemistry question with regard to brewing. It has to do with carbon dioxide being absorbed into a brew in a closed container. Does temperature effect the rate at which carbon dioxide is absorbed into a brew?

Originally posted by robbie carrobie
Ok, i have another chemistry question with regard to brewing. It has to do with carbon dioxide being absorbed into a brew in a closed container. Does temperature effect the rate at which carbon dioxide is absorbed into a brew?

the delusion rate of most gasses into liquids generally but not necessarily increases with increasing temperature. This is due to the molecules moving around faster as the temperature increases. However, the solubility of CO2 in water actually decreases with increase temperature of the water. I am not sure how that might effect the delusion rate of CO2 in the brew in a closed container and whether it would actually result in a net reduction in that diffusion rate. I am also not sure how the presence of alcohol in water might effect that. Anyone?

If you want just a rough idea of how the solubility of CO2 in water varies with temperature, which is not to be confused with how quickly it defuses into water from the gas-liquid interface, scroll about one-quarter down:
http://www.rmprocesscontrol.co.uk/Technical.htm
and see the graph.