Free_yO!
Rising Star
Hi everyone!
First sorry but I don't speak english very well.
My question is: when DMT salting with fumaric acid, it can do it in 2 different salts: hydrogen dmt fumarate and dmt fumarate. But in witch proportion? I tried to make calculations, but I'm not sure they are correct, something does not convince me. Someone would be able to correct them or give me clarification? Thank you!
pKa=-log Ka KaDMT = [H3O+][DMT] / [DMT H+] 8,68=pKaDMT KaDMT=2,08 * 10-9
Fumaric acid salts: DMTH+HF- hydrogen dmt fumarate 2(DMTH+)F2- dmt fumarate
Fumaric acid pka: pKa1=3,03 e pKa2=4,44
DMT pKa is greater than fmaric acid pka, so equilibrium is moved to the right.
Reactions are:
DMTH+ + H2O --> DMT + H3O+ H2F + H2O --> HF- + H3O+ HF- + H2O --> F2- + H3O+
KaDMT = [H3O+][DMT] / [DMTH+]
Ka1= [H3O+][HF-] / [H2F] Ka2=[H3O+][F2-] / [HF-]
DMT + H2F --> DMTH+HF- DMT + DMTH+ + HF- --> 2(DMTH+)F2-
keq1=[HF-][DMTH+] / [DMT][H2F]
keq2=[F2-][DMTH+]2 / [DMT][MDTH+][HF-] = [F2-][DMTH+] / [DMT][HF-]
multiplicand Keq1 and keq2 to [H3O+]/[H3O+] we obtain
keq1= Ka1 / KDMT pkeq1= pKa1 – pKDMTH
pkeq1= 3,03 – 8,68 = -5,65 keq1= 4,47 * 10^5
keq2= Ka2 / KDMT pkeq2= pKa2 – pKDMTH
pkeq2= 4,44 – 8,68 = -4,24 keq1= 1,73 * 10^4
This means that if we react DMT and fumaric acid in equal quantities (molar concentration) the formation of the first product (hydrogen fumarate of DMT) is favored for a ratio of 447000 to 1; the second product (DMT fumarate) for a ratio of 17300 to 1. But we don't work with equal molar concetration of DMT and fumaric acid, so how we have to change calculations?
If this calculations are correct, It means that when we are DMT fumarates salts they are 447000/17300= 25.83 hydrogen DMT fumarate each 1 DMT fumarate?
And what's happen with citric acid, that's triprotic acid?
Or maybe all this calculations are useless.....
First sorry but I don't speak english very well.
My question is: when DMT salting with fumaric acid, it can do it in 2 different salts: hydrogen dmt fumarate and dmt fumarate. But in witch proportion? I tried to make calculations, but I'm not sure they are correct, something does not convince me. Someone would be able to correct them or give me clarification? Thank you!
pKa=-log Ka KaDMT = [H3O+][DMT] / [DMT H+] 8,68=pKaDMT KaDMT=2,08 * 10-9
Fumaric acid salts: DMTH+HF- hydrogen dmt fumarate 2(DMTH+)F2- dmt fumarate
Fumaric acid pka: pKa1=3,03 e pKa2=4,44
DMT pKa is greater than fmaric acid pka, so equilibrium is moved to the right.
Reactions are:
DMTH+ + H2O --> DMT + H3O+ H2F + H2O --> HF- + H3O+ HF- + H2O --> F2- + H3O+
KaDMT = [H3O+][DMT] / [DMTH+]
Ka1= [H3O+][HF-] / [H2F] Ka2=[H3O+][F2-] / [HF-]
DMT + H2F --> DMTH+HF- DMT + DMTH+ + HF- --> 2(DMTH+)F2-
keq1=[HF-][DMTH+] / [DMT][H2F]
keq2=[F2-][DMTH+]2 / [DMT][MDTH+][HF-] = [F2-][DMTH+] / [DMT][HF-]
multiplicand Keq1 and keq2 to [H3O+]/[H3O+] we obtain
keq1= Ka1 / KDMT pkeq1= pKa1 – pKDMTH
pkeq1= 3,03 – 8,68 = -5,65 keq1= 4,47 * 10^5
keq2= Ka2 / KDMT pkeq2= pKa2 – pKDMTH
pkeq2= 4,44 – 8,68 = -4,24 keq1= 1,73 * 10^4
This means that if we react DMT and fumaric acid in equal quantities (molar concentration) the formation of the first product (hydrogen fumarate of DMT) is favored for a ratio of 447000 to 1; the second product (DMT fumarate) for a ratio of 17300 to 1. But we don't work with equal molar concetration of DMT and fumaric acid, so how we have to change calculations?
If this calculations are correct, It means that when we are DMT fumarates salts they are 447000/17300= 25.83 hydrogen DMT fumarate each 1 DMT fumarate?
And what's happen with citric acid, that's triprotic acid?
Or maybe all this calculations are useless.....