From Chemistry Towards Technology Step-By-Step From Chemistry Towards Technology Step-By-Step От химии к технологии шаг за шагом 2782-1900 96871 10.52957/2782-1900-2025-6-1-107-111 Научные статьи Scientific articles Научные статьи Effect of citric acid concentration on its dissociated and non-dissociated forms Effect of citric acid concentration on its dissociated and non-dissociated forms Мираминзода Фарида Miraminzoda Farida miraminzoda@mail.ru https://orcid.org/0000-0002-1349-2476 Рахимова Мубаширхон Rakhimova Mubashirhon

доктор химических наук;

doctor of chemical sciences;

 https://orcid.org/0000-0002-1390-2949 Файзуллозода Эркин Фатхулло Faizullozoda Erkin Fathullo

кандидат химических наук;

candidate of chemical sciences;

 https://orcid.org/0000-0002-0277-3758 Давлатшоева Джахонгул Асанхоновна Davlatshoeva Jahongul Asanhonovna

кандидат химических наук;

candidate of chemical sciences;

 Бобоназарзода Гулрухсор Бобоназар Bobonazarzoda Gulrukhsor Bobonazar еshova81@mail.ru

кандидат химических наук;

candidate of chemical sciences;

 Таджикский национальный университет Tajik National University Научно-исследовательский институт Таджикского национального университета Душанбе Таджикистан Научно-исследовательский институт Таджикского национального университета Душанбе Tajikistan 28 03 2025 28 03 2025 6 1 107 111 22 10 2024 07 02 2025 https://chemintech.ru/en/nauka/article/96871/view

The authors have studied the acid-base properties of citric acid by potentiometric titration at a temperature of 298 K and concentrations of CH3Cit(OH) of 0.01 and 0.02 mol/L. The results of potentiometric titration depend on the concentration of substances and the time of setting the equilibrium pH value of the titrated solution. The potentiometric method determined three carboxyl groups of citric acid corresponding to pKa1, pKa2, and pKa3. The values of citric acid dissociation constants for 0.02 mol/L concentration are 2.75, 4.45, and 5.82. The authors constructed the distribution diagrams of dissociated forms for both studied concentrations of citric acid. According to the data obtained, the distribution curves shift to the right on the pH scale with increasing acid concentration.

The authors have studied the acid-base properties of citric acid by potentiometric titration at a temperature of 298 K and concentrations of CH3Cit(OH) of 0.01 and 0.02 mol/L. The results of potentiometric titration depend on the concentration of substances and the time of setting the equilibrium pH value of the titrated solution. The potentiometric method determined three carboxyl groups of citric acid corresponding to pKa1, pKa2, and pKa3. The values of citric acid dissociation constants for 0.02 mol/L concentration are 2.75, 4.45, and 5.82. The authors constructed the distribution diagrams of dissociated forms for both studied concentrations of citric acid. According to the data obtained, the distribution curves shift to the right on the pH scale with increasing acid concentration.

 potentiometry citric acid concentration ionisation constants pH dissociated form undissociated (molecular) form functional groups potentiometry citric acid concentration ionisation constants pH dissociated form undissociated (molecular) form functional groups

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