If you have chemistry questions....

[squiggly]

Hello all, Squiggly here--resident chemistry asshole here at the farm :)

For the past year or so in my free time I have been compiling some useful chemistry information (and underlying concepts) as it regards cultivation--cannabis in particular (where I'm able to find specifics). I plan to really kick this project into high gear for this year, hoping to have something broad and publishable by the end of 2013.

In the mean time I have a few requests of you guys:

1. If you have a chemistry question--please either post it here. There is no such thing as a stupid question, if its something you want to know and don't, there is a high degree of certainty which says there are many people out there who are in that same situation. I want this guide to help all growers, beginning and expert, so its important for me to get an idea of what people do/don't/want to know.

2. If you know of any great resources which helped you to understand a chemical concept, a link to that in my inbox would be helpful. While I am pretty darn good at chemistry I am not ALWAYS good at teaching (although I like to think I take a piece-wise, one-concept-into-the-next approach). For this reason it will be helpful for me to check out methods that help people learn about chemistry and those which don't.

3. If you have a piece of chemical literature which you would like "translated" I would be happy to facilitate that. The scope and amount of material I can cover will be limited--I still have studies to pursue--so choose wisely.

As a thank you for helping me here, the fruits of my labor will be released for free (in a thread) here at the farm when it is completed. I'd like to offer, also, to answer any and all questions about chemistry here in this thread. I am more than willing to help those of you with more specific questions on an individual basis as well--as many farmers will certainly attest.

If your question is broad, please post it here so that everyone may share in the discussion. If it is a specific question relating only to your situation, please contact me through the message system.

Thanks!!!

P.S.

Topics open for question in which I have expertise:

Chemistry (my specialization is in organic synthesis--but I am knowledgeable elsewhere)
Biochemistry
Molecular Biology (intermediate)
Physics (intermediate)
Genetics (cursory)


This discussion is not limited to only the act of growing. Extractions, assays, other tests, lighting questions, etc, all apply here.

Be assured, if I am not fairly certain of the answer I am providing you--that I will say as much. It is not my intention to pretend I know more than I do, but rather to share that which I do know.

My inbox is ALSO open to submissions to this document--and as it will be in a thread when released, it will be a living document which can be added to and corrected over time if other information is found.

PLEASE DO NOT HESITATE TO CORRECT ME IF I GET SOMETHING WRONG--THIS PROCESS IS ABOUT FINDING REAL TRUTH, AND REAL EXPERIMENTAL/LITERATURE VALUES THAT ALL FARMERS MAY BENEFIT FROM. THERE IS NO "BEING CORRECT" IN THIS THREAD, THERE IS ONLY "PROVING CORRECTNESS."

 

[ttystikk]

Squiggly, you're far from being just another asshole on a forum- you're walking, talking proof of the value of community. I aspire to your level of expertise, and now generosity, at... well... anything! So, to kick things off here, I'm gonna ask a question about hot tub chemistry; I just drained and refilled my expensive plastic puddle today and it got me to thinking, 'why does it seem so different to pH balance a hot tub when I've been doing it in hydro for years?' Specifically, when the hot tub people talk about 'total alkalinity', they're NOT talking about actual pH, but rather something else. Is that something else a buffering capacity? Total dissolved salts in the water? Seemed strange to me.

This line of thinking got started when I noticed I was out of 'calcium hardness increaser.' I saw that it was comprised of calcium chloride in the hazardous materials statement, so I went and got my tub of 'pickling crisp'- a.k.a. food grade calcium chloride- and tossed some in. Since it's the same shit, it worked just fine- and a ridiculous savings over what they want for the stuff at the spa store!

So, if I want to replace some or all of the rest of my hot tub chemicals in the same way I've been finding inexpensive alternatives to hydro nutes, how would I go about it? That's what led me to thinking about 'total alkalinity'... or rather, wondering WTF they're talking about.

Post Script for all those haters to come who are wondering why I'm muttering about hot tubs in a grow forum; chemistry is chemistry, and it really doesn't matter whether we're mixing them in a tub to pour on our plants or to skinny dip in- the chemicals don't care. Having just today confirmed for myself that many of the chemicals and concepts are indeed exactly the same, I'm just wondering how to get square with the rest of it. Only Mr. Magoo would fail to see the parallels...

 

[soserthc1]

very cool and good idea squiggly , i will be posted up always willing to learn something new but chemistry is not anything i can comment on intelligently but I guess will see..... peace soser

 

[squiggly]

So, if I want to replace some or all of the rest of my hot tub chemicals in the same way I've been finding inexpensive alternatives to hydro nutes, how would I go about it? That's what led me to thinking about 'total alkalinity'... or rather, wondering WTF they're talking about.

Total alkalinity is a measure of the sum of the total stoichiometric equivalents of acid neutralizing base molecules in solution. Essentially it is a measure of how many molecules of base are in solution (in total).

pH is a measure of the H+ concentration in solution and pOH the measure of OH- ion concentration.

For example if you add 3mols of HCl into water, you will lower the pH--but the total alkalinity will be unaffected because HCl is a strong acid, and Cl- ions are unable to neutralize any acids (which is what makes HCl a strong acid essentially).

If you add say carbonic acid (lets just assume this molecule is stable for discussion--it is not) to a solution of pH 14 (very basic) it will lower the pH until it reaches about 10, at which point the ion left behind--bicarbonate--will begin to act as the base we all know it to be again.


In this situation because the pKa of bicarbonate is near 10 it will act as an acid until it gets below that value at which point it will go back to neutralizing acids.

In real life carbonic acid (H2CO3) rapidly decomposes to H20 and CO2--which is how we make the volcano experiement with baking soda work. When bicarbonate neutralizes an acid, it produces water and a gas.

Back to our situation wherein carbonic acid is stable.

If we add 3mol of carbonic acid to the solution--we will have contributed 3mol to total alkalinity--because we have left behind 3mol of bicarbonate which can neutralize an acid.

pH more discusses where the equilibrium lies RIGHT NOW in the system--while total alkalinity discusses WHAT WILL HAPPEN if we start adding acids in.

Hope that helps.

As for sourcing your other chemicals--just find out what the stuff is and do what you did here. Replace it with a cheaper product--but be sure to ensure that you're sourcing materials and comparing them carefully, if you plan to be bathing in this stuff you want to know EXACTLY what it is and how it was made (is it made with carcinogens and not intended to come into contact with the human body?--things like this).

 

[ttystikk]

Thank you- makes perfect sense as you explained it. As for the rest of the bottles, I'll do that- and I'll drop back in here with sources of those materials so you can tell me if they'll scour the very flesh from my bones or not, lol.

 

[sanvanalona]

O.k. I got one for ya buddy:

When harvesting herb, which I have been fortunate enough to do a few times in my life ;), I have noticed that a lot seems to happen to the quality of the plant post harvest. Example, I have noticed quite a difference in taste and high when trimming my herb wet as opposed to letting the herb hang dry for 2-3 weeks, when done the latter the herb is far superior imo. So not to start argument here over personal belief but from a strictly scientific pov: can there be a chemical change in the plant post harvest that could be adversely affected if trimmed or "bruised" while wet?

Hope this is not too simple of a question for you, I know what I like from my experience but I am curious if science can back up my theory.

 

[Seamaiden]

I have a question on an alchemical gardening 'tip' I'm trying, but everyone else is jumping in on the question train before me.

Squigs, when you can get to it, here's my question. I'm taking white vinegar and freezing/thawing 3x. This is supposed to get me a more concentrated acetic acid. I have not maintained my pH probe so I can't tell you what the actual pH of the solution is. I then crushed fresh, washed eggshells and put them in the Final Solution. They've been there 3-4 weeks and while I've been shaking daily, and while at the beginning there was QUITE a bit of reactivity, there is little now.

My question(s) are this: First, what am I getting, exactly, by doing this first method? I can see that the volume of crushed shell is dramatically reduced, though not eliminated. What am I ending up with using the acetic acid+egg shells, though?

Second question: Would I gain better access to both the Ca and P present in shells if I were to bake or char the shells prior to putting them into the concentrated acetic acid?

Third, is there a better way to do this (make use of leftover shells besides composting)? My soils are Ca- and I often experience problems associated with Ca-, including in my tomatoes, peppers and squash quite a bit of blossom end rot that is *not* related to watering.

Please note: I am working towards acquiring my organic certification for my market garden (Schedule F is for Farmer, mang!), and because I'm working land that has never been cultivated before if I can maintain a paper trail that shows that NO petro-chemical/unapproved products have been used, then it will be that much easier to acquire my certification.

 

[squiggly]

can there be a chemical change in the plant post harvest that could be adversely affected if trimmed or "bruised" while wet?

Certainly. Chopping the plant does not render all of the enzymes/other proteins in the plant inactive immediately. In fact a good portion of the plant remains alive for quite some time after chopping. It does have trouble moving things about in the plant (nutrients/etc) without the root system in place, however because we're mostly chopping leaves--I'd assume, safely I think, that yes there is some transport that takes place from those leaves while drying if they are left alone.

I don't know that the proper term to use is "bruising"--although this is definitely categorically possible as well, depending on the nature of the damage and what the, still living, tissue's response will be. If, for instance, necrosis or something resembling it set in post harvest due to an injury, that would certainly have an effect on the taste.

What I'd assume is the culprit is more likely the removal of those nutrients the leaves are storing (or perhaps removal of a storage area where some nutrients/chemicals may have been pumped [again the leaves]).

I think initially the hypothesis is not outlandish, but proving it would require some heavy, and probably prohibitively expensive, analysis.

Hope that helps.

 

[squiggly]

My question(s) are this: First, what am I getting, exactly, by doing this first method? I can see that the volume of crushed shell is dramatically reduced, though not eliminated. What am I ending up with using the acetic acid+egg shells, though?

This is the equation you are looking for:

CaCO3+ 2H+ -> Ca+2 + H2O +CO2
You are getting Calcium ions (in solution) and CO2 gas. You are also getting H2O.

As the reaction progresses acetic acid is being neutralized--and the H+ content of the solution is dropping (the pH is moving up)--at the same time you are producing H2O which is diluting the acid further (also pushing pH up).

Eventually the stuff won't be acidic enough to dissolve anything else.

There are a few possibilities here:

1. You have added more CaCO3 equivalents, then you have H+ equivalents (acid)---essentially rendering the solution neutral and the reaction complete. Its important to remember that these reactants have finite values. As acid does its thing--it changes its chemical composition (generally) and is no longer acid when its done. Everything is moving down this thermodynamic well towards greater stability as it regards molecules. Once the stuff has reacted, everything should end up in a more stable, equilibriated, state than it began in.

2. What is left over is particulate matter, fats, proteins (which are selectively soluble depending on pH, generally speaking), waxes, and other insoluble minerals (egg shells do contain some pure calcium which is not going to be ionized by a weak acid like acetic--this is because it is more stable in that state than as an ion. Stability is in this order Ca > Ca+2 > CaCO3 in this particular environment.

Here is where I could talk for 2 hours about oxidation states, but instead I will simply explain to you that in a reducing environment (acidic) the more oxidized molecules will be less stable (because reduction is the opposite of oxidation). In this triplet, CaCO3 is the most oxidized--so its out the door first.

Honestly I want to say so much more here, but this is really something which needs to be discussed after a bit of groundwork has been laid in terms of chemical concepts--oxidation states and oxido-reductive reactions are typically done at the end of gen chem II. At the very earliest you'd get into this at gen chem I right before the final.

It is really important to understand solubility implicitly to really go through the discourse I'd like to have here.

3. Your solution is saturated with ions and cannot accept anymore.

Let's say you run a reaction which occurs in solution and as it comes to completion you are low on reactants and high on products. The completeness to which this reaction goes (many if not most reactions stop before all reactants have been used up) depends on something known as an equilibrium constant.

If you wait until the reaction is essentially done, and then add in the same amount of reactants you began with (into the same solution/reacting vessel) the reaction will proceed slower the second time, due to the excess of products already present. Concentrations also play a role.

If you throw a large excess of eggshells into your acid at once- the reaction will proceed much more quickly. The same is true for adding more acid to the same amount of eggshells.

This is follows a concept known as Le Chatlier's Principle which essentially says that equilibrium is shifted across the "yields" sign of a chemical equation such as above as though it were a balance.

I recommend this animation:

One useful way to conceptualize this is to look at an industrial standard. Some reactions only produce VERY LITTLE of a targeted product for a large reaction. due to the unfavorability of such a reaction the desired product is constantly drawn off of the vessel as it is produced. This is to keep equilibrium shifted to the RIGHT (or products side) of the reaction.

In this case the reaction we're looking at by which Ca+2 is produced, is strongly favored to the right. This is due to the rapid evolution of the initial product (H2CO3) to H20 and Co2--so essentially there is very little equilibrium to this reaction, it is strongly favored because half of the products are being constantly "drawn off" automatically by nature--however the above discourse has been to convince you of the idea that having more Ca+2 ions in solution can still slow down or impede the reaction, despite how spontaneous and thermodynamically favorable it is.

I have been really vague here to be honest--I'm explaining this as though you are 3rd year undergraduate chem major, there are a litany of underlying concepts that i'm implying which I literally don't have the space in one post to explain.

Second question: Would I gain better access to both the Ca and P present in shells if I were to bake or char the shells prior to putting them into the concentrated acetic acid?

Its possible--however you made also produce and solubilize some substances that you don't want in there. There is a lot of stuff in eggshells for as simple as they seem.

Third, is there a better way to do this (make use of leftover shells besides composting)? My soils are Ca- and I often experience problems associated with Ca-, including in my tomatoes, peppers and squash quite a bit of blossom end rot that is *not* related to watering.

Calcium carbonate should be available to a number of different beneficial bacteria. Amending soil with both crushed, and chipped eggshells would provide a "slow release" calcium stream (and the chipped shells would be "ultra slow release")

It's possible eggshells will act to slightly buffer soil pH--don't ask me at which pH, though.

Macroscopic really isn't my shit, unfortunately--this one is probably better left to a pro composter.

 

[Seamaiden]

Heh... I did well in high school chemistry, but I think I'm with you as far as equilibrium, not sure if I'm following the rest very well.

I did forget to mention that along with being Ca-, my irrigation water is very high in both (home aquarium kit tested, via colorimetric titration, specifically Tetra Laborette kit, rather rough, but it suited my needs) general and carbonate hardness (measured as degrees dKH). My observations suggest that it's either CaCO3, CaMgCO3, or a combination of CaCO3 and MgCO3. In fact, we're within a mile radius of a park called Black Chasm, that's operated and overseen by the UCDavis Geology Department, and it's a gypsum crystal cave (yet I sit on all this fucking clay that requires what to break up? Gypsum, according to the old-timers).

In any event, back to the water--it's all I'm irrigating my outdoor cannabis and vegetable/fruit crops with, and I've seen a paper that's discussing the problems with irrigating using high carbonate-content water. If I understand you correctly, I'm getting yet more CaCO3, or in other words, more fucking carbonates, yes?

I don't need more carbonates, I need more (organic and available) Ca! Bloody fucking hell, this shit is a pain in the ass sometimes, I swear. <facepalm>

In any event, you've described what I've been observing in this little pint jar I made up of the concentrated acetic acid and eggshells. For shits & giggles I did one of old pork rib bones in a quart jar next to it. Lotsa meat & gristle on those, not much bubbling anymore.

Here's a link to the alchemy site I used as my pictographic for the method. I actually read an article in Acres, USA, on the method first.
http://www.alchemywebsite.com/distillation_of_vinegar.html

 

[silverhaze]

Squiggly,
My question is about the shelf life of nutrients as it relates to climate changes. While we all know it is recommended to keep your nutes in a cool dark place, it is not always possible; especially when you consider the heat we've all been experiencing lately. I had a time of transition where I was not growing and some of my products had to sit in a hot garage. Will nutrients quickly degrade when exposed to high temperatures? I would guess that liquid ferts would degrade faster than powders - is there any way to tell if your nutes have gone bad aside from physical changes? How about enzyme products like Hygrozyme/Cannazyme? Nothing in my line up is over one year old but some of them have been exposed to substantial temperature changes. Clearly, I don't want to throw away expensive nutes but using ineffective or counter productive products could be far more expensive in the long run. Thanks in advance.

 

[squiggly]

If I understand you correctly, I'm getting yet more CaCO3, or in other words, more fucking carbonates, yes?

I don't need more carbonates, I need more (organic and available) Ca! Bloody fucking hell, this shit is a pain in the ass sometimes, I swear. <facepalm>

Read the equation again:

Reactants Products
CaCO3+ 2H+ -> Ca+2 + H2O +CO2

You are ending up with Ca+2, which is what you are after (this is the plant-available form of calcium).

This reaction does not ultimately follow an exact equilibrium, because the products side is thermodynamically favored. However, if there is too much Ca+2 present in solution the reaction can stop. Explaining this would require a healthy lesson on thermodynamics--and several diagrams.

Sadly I've got some NMRs to look through and annotate for my professor so I can't do that at the moment :)

I think this should suffice, you are doing the proper thing to get what you want--try using more acid initially to fully dissolve the eggshells. Failing that, strain out the remaining particulate matter and get to feeding.

As for your water, I'm betting you've got CaCO3 and MgCO3 in there.

 

[squiggly]

Will nutrients quickly degrade when exposed to high temperatures?

This question is exceptionally vague. Short answer, there is a distinct possibility that the answer is yes. Heat tends to overcome thermodynamic barriers to reactions--and can speed up degradation. If the chemicals in question are already prone to spoilage, then heating them will certainly speed things along generally speaking.

Most nutrients consist of a chemical soup--it's not really possible to tell you what will degrade and what won't without specifics.

I would guess that liquid ferts would degrade faster than powders - is there any way to tell if your nutes have gone bad aside from physical changes?

If only it were that intuitive. Solids can be equally as reactive as liquids--and sometimes degrade even more easily. It all depends on the chemistry, and this is again substance specific. As for telling if nutes are bad--without very expensive machinery and knowledge of the original absolute composition of the solution, no. Physical changes are your only guide (smell, texture, pH, etc.)

How about enzyme products like Hygrozyme/Cannazyme? Nothing in my line up is over one year old but some of them have been exposed to substantial temperature changes.

Enzymes are proteins, and proteins can be denatured by heat (this means they unfold and lose their specific shapes which render them active). If the heat is reduced many proteins have the ability to spontaneously fold back into their original shapes--however some enzymes require chaperone molecules and proteins to fold properly. Again this depends on the absolute structure of the specific enzyme--however again without expensive equipment and substantial knowledge about the protein in question (proteins are insanely complex, it is hard to know what is going on to be honest) it will be even more difficult to surmise whether an enzymatic product has gone bad.

That said, bad enzymes are not likely to harm anything.

 

[cemchris]

Where or how would someone go about testing ISO or BHO for remaining solvent in a non med state? That's a pretty vague question that's almost not chemistry related.

 

[squiggly]

Where or how would someone go about testing ISO or BHO for remaining solvent in a non med state? That's a pretty vague question that's almost not chemistry related.

There is not a feasible option for this sans expensive/difficult to construct equipment.

The chemical compounds are too similar to extract them from one another selectively for an assay.

You could certainly buy an IR spectrophotometer and I could easily train you to spot the chemical signatures of these compounds on a spectrum from said device--without that or another analytical instrument (this would be the cheapest one to buy that will work for this purpose), this is essentially impossible.

The best way to ensure that you have removed all residual traces is to properly purge the material.

Extracting into a more easily removed material such as methylene chloride or chloroform is also an option.

 

[swisscheese]

I have been toying with some triacontanol and bap6 from ebay any experience or tips with them?

 

[squiggly]

I have been toying with some triacontanol and bap6 from ebay any experience or tips with them?

Watch adding TRIA in flower--it will tend to produce stretchiness and may contribute to airier flowers--especially if it is used earlier on. It may help stack on weight late in flower (last week or two). It is a wonderful addition in veg--but the concentration of it MATTERS, and how its delivered is important. You'll want to do some intense reading up on that--there is a thread where we talked about triacontanol a few months back I'll see if I can dig it up, and post back.

Edit: Here is the link

https://www.thcfarmer.com/community/threads/triacontanol-what-it-is-where-to-find-it.47363/

More work should be done to check up on this insight and confirm it--but I imagine most people would rather experiment with such things rather than test them on entire crops. I do want to emphasize that my position has shifted a bit based on more recent reading; adding triacontanol may be beneficial if it is added late in flower. Previously I have taken the position that it is always bad in flower, and I wanted to clarify that.

As for Bap6, let me read up a little bit as I've got some free time--and I'll get back within in hour or so.

 

[rick ratlin]

awesome thread squiggly! not sure if this applies, but any recommendations on removing nutrient salt build up on plastic trays? Not lazy, overused fertilizer build up, but the kind that just won't come off. My guess is that it is silica, but not 100% sure.

 

[squiggly]

I always go in this order when I wanna get something off.

Acetone -----> weak base ------> weak acid --------> strong base -------> strong acid

once its off, finish up with ethanol.

Obviously you'll want to shy away from the strong acids and bases for plastic.

If its thick enough, you can always just scrape it off--coming at it with some olive oil might do the trick as well.

 

[cemchris]

There is not a feasible option for this sans expensive/difficult to construct equipment.

The chemical compounds are too similar to extract them from one another selectively for an assay.

You could certainly buy an IR spectrophotometer and I could easily train you to spot the chemical signatures of these compounds on a spectrum from said device--without that or another analytical instrument (this would be the cheapest one to buy that will work for this purpose), this is essentially impossible.

The best way to ensure that you have removed all residual traces is to properly purge the material.

Extracting into a more easily removed material such as methylene chloride or chloroform is also an option.

Haha how much are they bout 20 g's? Yeah this is more of a curiosity of the methods used where it seems like people just go one something they heard. I have followed yours and graywolf's posts i the other threads and they were very informative. Thx for the help.