Nullis
Moderator
Not yet. I've been studying for placement exams, I just read about organic chemistry or soil sciences when I get the chance. More recently I've had a son to help support and some health issues.
To answer Patt, I use lime probably for some of the same reasons you do. In particular though, I usually mix (recycle) my soil or customize/blend one or two bagged mixes for container growing. Either way I am adding coco coir, and sphagnum is another main ingredient in the base mix.
I use rain water typically ~10 ppm, no mineral content. The plants I grow tend to get fairly large. Also, I consider that the microbes in the media also require minerals. Bacteria and fungi too require Calcium and Magnesium cations for growth and proper functioning. Even roles for trace elements are becoming more apparent. Magnesium, for example, living cells need it not only to store ATP, but for their DNA, RNA, enzymes. The common genus of soil bacterium Bacillus, obligate aerobes or facultative anaerobes all of which are capable of going to endospore and they need Calcium to do this effectively. Additionally, some N-fixing bacteria (Azotobacter) prefer a soil pH slightly above 7.
On the topic of Calcium; I should note that I suppose you could call ionic Calcium 'elemental', but it really isn't ever strictly so I don't believe it would be correct to. Also, Magnesium (in dolomite/dolomitic lime) is ionic just the same. Ions are charged particles or chemical species, with either a net + charge for a cation or a net - charge for an anion. Ca and Mg can both occur as bivalent, monatomic cations. Ca and Mg are both metals and can ionize, losing two of their valence (outer shell) electrons to another (non-metal) species to make a neutral ionic compound or salt. In CaCO3 for example, carbonate is the non-metal anion and it is polyatomic, CO3--, with a net negative charge (also divalent).
Both Ca and Mg can loose 2 electrons to a carbonate anion, giving the respective cation bonded in ionic (electrovalent) fasion to the carbonate. This is different than covalent bonding, in which electron pairs are shared between molecules, and those bonds are generally much stronger. The Carbonate anion itself does feature covalent bonds: those are the bonds that hold the carbonate together. Bonds between the metal and non-metal are strictly ionic, though. Same thing goes for table salt: sodium (Na) is the metal and chlorine is the non-metal, and the bond is ionic. Gypsum is calcium sulfate (CaSO4), and in this case sulfate (SO4--) is the non-metal. Natural gypsum has water (hydration) trapped within its crystal.
As solids, ionic compounds arrange in a crystal-lattice structure. While in solution they dissociate (ions separate, more or less depending on solvent, temp, pressure, etc.) and the ions behave independently of one another. A solid ionic substance can take on more than one mineral\crystal form, with the other forms referred to as polymorphs. For (pure) CaCO3 the other common form (polymorph) is Aragonite, and a rare polymorph is Vaterite. The crystal/lattice systems are the only real differences between them; just the way the molecules arrange themselves. Going back to pure dolomite, in that case it is just that Ca and Mg cations are alternating. Physical/chemical properties are still generally the same as for other carbonates.
To answer Patt, I use lime probably for some of the same reasons you do. In particular though, I usually mix (recycle) my soil or customize/blend one or two bagged mixes for container growing. Either way I am adding coco coir, and sphagnum is another main ingredient in the base mix.
I use rain water typically ~10 ppm, no mineral content. The plants I grow tend to get fairly large. Also, I consider that the microbes in the media also require minerals. Bacteria and fungi too require Calcium and Magnesium cations for growth and proper functioning. Even roles for trace elements are becoming more apparent. Magnesium, for example, living cells need it not only to store ATP, but for their DNA, RNA, enzymes. The common genus of soil bacterium Bacillus, obligate aerobes or facultative anaerobes all of which are capable of going to endospore and they need Calcium to do this effectively. Additionally, some N-fixing bacteria (Azotobacter) prefer a soil pH slightly above 7.
On the topic of Calcium; I should note that I suppose you could call ionic Calcium 'elemental', but it really isn't ever strictly so I don't believe it would be correct to. Also, Magnesium (in dolomite/dolomitic lime) is ionic just the same. Ions are charged particles or chemical species, with either a net + charge for a cation or a net - charge for an anion. Ca and Mg can both occur as bivalent, monatomic cations. Ca and Mg are both metals and can ionize, losing two of their valence (outer shell) electrons to another (non-metal) species to make a neutral ionic compound or salt. In CaCO3 for example, carbonate is the non-metal anion and it is polyatomic, CO3--, with a net negative charge (also divalent).
Both Ca and Mg can loose 2 electrons to a carbonate anion, giving the respective cation bonded in ionic (electrovalent) fasion to the carbonate. This is different than covalent bonding, in which electron pairs are shared between molecules, and those bonds are generally much stronger. The Carbonate anion itself does feature covalent bonds: those are the bonds that hold the carbonate together. Bonds between the metal and non-metal are strictly ionic, though. Same thing goes for table salt: sodium (Na) is the metal and chlorine is the non-metal, and the bond is ionic. Gypsum is calcium sulfate (CaSO4), and in this case sulfate (SO4--) is the non-metal. Natural gypsum has water (hydration) trapped within its crystal.
As solids, ionic compounds arrange in a crystal-lattice structure. While in solution they dissociate (ions separate, more or less depending on solvent, temp, pressure, etc.) and the ions behave independently of one another. A solid ionic substance can take on more than one mineral\crystal form, with the other forms referred to as polymorphs. For (pure) CaCO3 the other common form (polymorph) is Aragonite, and a rare polymorph is Vaterite. The crystal/lattice systems are the only real differences between them; just the way the molecules arrange themselves. Going back to pure dolomite, in that case it is just that Ca and Mg cations are alternating. Physical/chemical properties are still generally the same as for other carbonates.
) I would think lobster is on par with the crab.
