Is Mg + EDTA spontaneous?
454058
Yes, provided that the pH is high, say around 10.
739325
According to Sigma-Aldrich the solubility of MgCl2.6H2O is 1M at 20C (or 20.3030 g/100ml solution), so it shouldn't be possible to prepare 4.5 M MgCl2 in just water. If there are more solutes involved which might increase the solubility of MgCl2 try dissolving those first and then the MgCl2.\n\nYet I saw some papers using 4.5 or 2.5 M...\n\nI don't know why there is this discrepancy between sigma-aldrich and the solubility provided in the link in the above answer which would correspond to 8 M if you consider 100ml of solution and not water. In reality you would have a significant change in volume when you add so much salt and the solubility would be much less but I don't know exactly how much. If you consider 167g of MgCl2.6H2O then you are adding 88.8 g of water which means that the total volume is at least 189 ml and thus the maximum concentration is 4.3 M.\n\nWikipedia gives a different number; 54.2g/100ml at 20C, without specifying if it is for the anhydrous or hexahydrate... so it would be 5.6 or 2.6M respectively... \n\nWhat a mess !!!\n\nMaybe you should also post the question in biology, since someone who has been doing such purifications can clarify the issue.\n\nAnother idea would be to prepare a 100ml saturated solution according to the lowest reported solubility (that of sigma-aldrich) using a 250 ml volumetric cylinder, and then from a pre-weighed amount of MgCl2.6H2O keep adding powder slowly until it doesn't dissolve any more. Weigh the powder that is left in order to find how much you dissolved, measure the final volume and calculate the molarity. If you achieve higher than 4.5 M, dilute.\n\nOR\n\nprepare a 4 M if the amount of powder that you couldn't dissolve is very small.\n\nor \n\nprepare 450ml of 1M and evaporate to 100ml of solution while praying that there will be no precipitation...\nThat's very desperate but I am running out of ideas...\n\nI must say the whole story is very fishy (finding very different solubility values)\n\nI'd go mad too...
883304
Na2EDTA is a complex molecule. Its name stands for ethylenediaminetetraacetic acid – disodium salt. The formula is Na2C10H14N2O8. Even though its name and structure are complex, you only need to know that: EDTA reacts with Ca+2 and Mg+2 in a one to one ratio as follows:\n:Ca+2 + EDTA-2 -----> CaEDTA\n\nMg+2 + EDTA-2 -----> MgEDTA\nThe formula mass of Na2EDTA dihydrate is 372.24 g/mole.Na2EDTA comes as a dihydrate(absorbs water from the atmosphere) which is efflorescent (literally means "bursting into flower" but in this case just means that it forms bubbles), you cannot reliably weigh out the desired number of grams. The salt may be fully, or only partially, hydrated at the time you weigh it. The result is that you cannot be certain that you have prepared the proper strength reagent of EDTA..therefore: you need to standardize the solution  The results of the titration is reported as mg of CaCO3/liter.\nTo convert Calcium plus Magnesium (meq/L) Hardness as CaCO3 (mg/L) 50\nOf course since Fe and Mg and Ca and other metals are also present in water it is better (more accurate) to titrate for each metal species individually and calculate the hardness using the results of the individual results. EDTA hardness is sometimes referred to as "Total hardness"and is reported as " Hardness as mg/l CaCO3."
243790
EDTA stands for ethylenediaminetetraacetic acid.  It has a very strong affinity for calcium ions in aqueous solutions.  When blood is drawn into a tube containing EDTA, calcium ions in the blood are almost irreversibly bound to the molecules of EDTA.  Calcium ions are a critical component in the biochemical cascade that results in blood clotting.  The EDTA makes the calcium ions unavailable, hence the blood will not clot.\n\nEDTA and related chemicals are known as chelating agents (the term is derived from the Greek word for "claw") because of their high affinity particularly for metals such as copper and lead.  EDTA is sometimes administered intravenously in cases of acute lead or mercury poisoning; the metal binds strongly to the molecules of EDTA, and the EDTA-metal complexes are excreted via the kidneys.  Such treatment begun soon after exposure to lead may prevent nervous system damage and minimize deposition of lead in the bones, where it is stored and slowly released over long periods of time if not gotten rid of.
1077836
none salt cause high bloodpressure and stress
874472
EDTA is a chelating agent which chelates Mg ions. Mg ions are reqd as cofactors for enzyme which degrades DNA.Hence addtion of EDTA chelates out Mg2+ of such enzymes making them inactive so that DNA is not degraded or broken down, so one can get entire DNA without breakage during DNA extraction process.
767332
If a reaction is spontaneous, that means it will occur without adding energy, the more negative delta G is, the more spontaneous it is. If delta G is positive, that means that the reactant is more stable at its present state and therefore for a reaction to occur, you must add energy to push the reaction forward. This would be non spontaneous because of the need of energy to complete the reaction.
83425
An imbalance of the other major blood chemicals which are calcium, sodium and potassium.  If your potassium level is too low, your magnesium level can be elevated.  Potassium is available in potatoes and bananas.  Calcium is in milk and cheese and the small bones in tiny fish like sardines and anchovies.  Sodium is in salt.  They work together in your body and an imbalance in one can effect the absorption or elimination of the others.
955628
For the reaction:\n\nMgO + 2 HCl  -->  MgCl2 + H2O\n\nThe temperature should go up, not down.  Only the initial and final temperature are needed.\n\nTypical values for students are between 110 an 150 kJ/mol MgO.  This is typical, not the best that can be done.
135714
I have done some research on this because my mom has been stricken with Alztiemers. Drs dont think its aluminium. They say most the time its triggered from stroke or stress. They dont know for sure the cause.
131743
The formation of PhMgBr is a redox reaction.  The two electrons of magnesium metal are added to the PhBr bond to make Ph-Mg-Br.  Then you added this in solution to the dry ice (solid O=C=O).  The electrons between Ph and Mg add to the carbon of the CO2.  The electrons from one of the pi bonds moves out to the oxygen so that you have PhC(O)O- where the (O) is still doubled bonded to the C.  After the reaction was complete, you added water to protonate the O minus.  This completes the reaction.  Since you are in organic lab, you should still have an organic textbook.  There is likely a mechanism drawn out in any organic textbook you can find.
180379
Like the refractive index of urine (specific gravity) it depends on the concentration of the dissolved solutes. Other than using it as a baseline in the assays mentioned above, I can think of little purpose in performing it. It is non-specific, and even a reading in the 'normal' range would not preclude an electrolyte imbalance.
517398
Magnesium and trace amonts of mercury.
290781
MgSO4(s) + 2HCL(aq) ---> H2SO4(aq) + MgCl2 (aq)
339232
Yes, the reaction would spontaneously occur because Sn is higher on the activity series than Ag.\n\nSn(s) + 2AgNO3(aq) => Sn(NO3)2(aq) + 2 Ag(s)\nThe net ionic is\nSn(s) + 2Ag+(aq) => Sn+2(aq) + 2 Ag(s)\n\nI don't remember the oxidation number for Sn.  2 sounds about right.\n\nIt would turn a silver nitrate solution to a tin nitrate solution, and you'd see metallic silver precipitate out.
823331
Vitamin B6 and Magnesium both assist with promoting nerve health. \nWhen I was advised by a specialist to take B6, I asked about side affects and was told there weren't any. \nThat was not true. I developed a problem with needing to urinate a little too often. Like every 10 to 15 minutes. A real problem when I'm out.\nResearching B6 on the internet, I discovered that it is a diuretic. It makes you pee. \nSo much for specialists. Although he didn't know that it came in different dosages either. When I asked him how many milligrams, he had to look it up. He actually asked ME - "Does it come in different strengths?" DUH.
794643
1. highter since given weight of magnesium looks to be a larger percent of finished product.\n2.It would depend on molecular weight of other reactants.  If they were heavier than Oxygen the Mg would seem to be a lower percentage.  If only other possibility for Rx was with nitrogen and ratio of recatants was the same as with Oxygen(unlikely) then the resulting compound would be lighter than MgO making the Mg percent higher.\n3.  Mg oxydizes in air at room temp.  This white film was MgO already oxydized which would interfere with your results, raising the calculated percentage of Mg.