BushyFromOz Posted August 7, 2012 Author Posted August 7, 2012 No worries mate. It wouldn't matter if you were doing it for the hell of it. Unfortunately, all of the systems of measurement are rather arbitrary and we often run into the problem of different systems and dimensions being used. Imagine my horror when somebody stated a patient's blood sugar was 6 for the first time in front of me only to follow it after my reaction with "what, 4-8 feeling great." Yeah. Nearly everything ive seen is in SI units, so either grams or mol/mmol, so the mEq really threw my head into a spin.I cant imagine why anyone here is using nanograms for troponin when nearly everything is done in mmol... must have got a discount on whatever machine the are using as it was one of those iSTAT type things. This is the problem with the text books i have, nearly all uUS based so using measurements that are i am unfamiliar with, its like having to use a shity socket set when all you have is metric but your nice sidchrome gear is in imperial
systemet Posted August 7, 2012 Posted August 7, 2012 (edited) In solution it is expressed as a concentration of 1 mol of the compound per litre pf solution? so .9% saline is .9% of 1 gram (mol) of NaCl?? I think the main thrust of the post was about milliequivalents<->mmol conversion, and has already been answered in detail. I just wanted to add that the expression of solution concentrations as percentages is a little different. A 1% solution is by definition 1g in 100ml. It has nothing to do with millequivalents or molarity / molality. So a 0.9% sodium chloride solution, is 0.9g of sodium chloride with water added to a final volume of 100 ml. You could do the math and convert this to a molarity, in which case you have 154 mmol of Na+, and 154 mmol of chloride. But, this is particular to 0.9% NaCl. If you were to make 0.9% dextrose, for example, you'd have a different molarity. [(9g / 100ml ) / (58.44 g/mol)] * (1000ml / 1L) * ( 1000 mmol / 1 mol) = 154 mmol/L (Here 58.44 g/mol is the molar mass of sodium chloride. Use something with another molar mass, e.g. CaCl2, and the answer will be different). Edited August 7, 2012 by systemet
BushyFromOz Posted August 8, 2012 Author Posted August 8, 2012 (edited) I think the main thrust of the post was about milliequivalents<->mmol conversion, and has already been answered in detail. I just wanted to add that the expression of solution concentrations as percentages is a little different. A 1% solution is by definition 1g in 100ml. It has nothing to do with millequivalents or molarity / molality. So a 0.9% sodium chloride solution, is 0.9g of sodium chloride with water added to a final volume of 100 ml. You could do the math and convert this to a molarity, in which case you have 154 mmol of Na+, and 154 mmol of chloride. But, this is particular to 0.9% NaCl. If you were to make 0.9% dextrose, for example, you'd have a different molarity. [(9g / 100ml ) / (58.44 g/mol)] * (1000ml / 1L) * ( 1000 mmol / 1 mol) = 154 mmol/L (Here 58.44 g/mol is the molar mass of sodium chloride. Use something with another molar mass, e.g. CaCl2, and the answer will be different). I realised the mess up after i posted the question, but the edit function had dissappeared by then, but thanks for the heads up bro Edited August 8, 2012 by BushyFromOz
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