DMT-Nexus member
Posts: 60 Joined: 24-Oct-2015 Last visit: 17-Apr-2022
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Bodhisativa wrote:some one wrote:Quote:EDIT: I did the titration. I used 500ml of my stock solution HCl, and titrated against my stock solution of NaOH. HCl is 0.001M and NaOH is 5M.
Within 3mL of NaOH, the equivalence point was reached. At 5mL, the pH was 11. At 10mL the pH plateaud at 12, but I'm using a crappy pool pH meter. The guide has bee edited.
Converting your titration experiment concentrations to grams: HCL = 0.001 mole/liter * 0.5 l = 0.0005 mole = 0.0005 mole * 36.46 g/mole = 0.02 gram NaOH = 5 mole/liter * 0.003 l = 0.015 mole = 0.015 mole * 39.9 g/mole = 0.60 gram That's my point... In a 500 ml solution, it takes 0.02 gram of HCL to reach pH 3. Adding 0.60 gram of NaOH to that solution raises the pH to 12 (you say). Which makes sens as all it takes is 0.40 gram of NaOH to reach a pH 12 in 1000 ml of water (0.01 M) - according to the link you posted Again, if that's so and 0.40 g of lye reaches pH 12 which is sufficient to extract, why are all teks using 50-100g of lye (factor 100-200 more)? For my HCl stock solution, I pipette 1mL of 320g/L HCl into 10L of distilled water. That's brings the pH between 3-4. As to why most teks use huge amounts of lye, I honestly don't know. Maybe because a lot of teks are based on other teks. My guide is heavily inspired from MAX ION and Earthwalkers. So I just used similar quantities. I'll do another extraction using absolute minimal quantities of everything and I'll post my results. Could the amounts of acid and lye have something to do with the buffer capacity of the root bark. Most plants have a certain buffer capacity so to counteract this buffering effect you need more acid/base than a theorethical pH calculation in water. I don't have a pH meter at home so I'm not sure about the buffer capacities of root bark. Disclaimer: Everything I say/write/post/think about is fiction. All said activities are intended for educational or entertainment purposes only.
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Don't Panic
Posts: 756 Joined: 28-Dec-2014 Last visit: 01-Oct-2022 Location: Everywhen
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Thistle Elf wrote:Bodhisativa wrote:some one wrote:Quote:EDIT: I did the titration. I used 500ml of my stock solution HCl, and titrated against my stock solution of NaOH. HCl is 0.001M and NaOH is 5M.
Within 3mL of NaOH, the equivalence point was reached. At 5mL, the pH was 11. At 10mL the pH plateaud at 12, but I'm using a crappy pool pH meter. The guide has bee edited.
Converting your titration experiment concentrations to grams: HCL = 0.001 mole/liter * 0.5 l = 0.0005 mole = 0.0005 mole * 36.46 g/mole = 0.02 gram NaOH = 5 mole/liter * 0.003 l = 0.015 mole = 0.015 mole * 39.9 g/mole = 0.60 gram That's my point... In a 500 ml solution, it takes 0.02 gram of HCL to reach pH 3. Adding 0.60 gram of NaOH to that solution raises the pH to 12 (you say). Which makes sens as all it takes is 0.40 gram of NaOH to reach a pH 12 in 1000 ml of water (0.01 M) - according to the link you posted Again, if that's so and 0.40 g of lye reaches pH 12 which is sufficient to extract, why are all teks using 50-100g of lye (factor 100-200 more)? For my HCl stock solution, I pipette 1mL of 320g/L HCl into 10L of distilled water. That's brings the pH between 3-4. As to why most teks use huge amounts of lye, I honestly don't know. Maybe because a lot of teks are based on other teks. My guide is heavily inspired from MAX ION and Earthwalkers. So I just used similar quantities. I'll do another extraction using absolute minimal quantities of everything and I'll post my results. Could the amounts of acid and lye have something to do with the buffer capacity of the root bark. Most plants have a certain buffer capacity so to counteract this buffering effect you need more acid/base than a theorethical pH calculation in water. I don't have a pH meter at home so I'm not sure about the buffer capacities of root bark. The pH of the acid and the root bark did not deviate from the pH of the stock solution of acid. If there is a buffering effect, it seems it is negligible. I have not tested this thoroughly, though. I'll make sure to investigate this when I do my next extract. Thanks! "A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools."
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