Related Experiment Video
Updated: Jun 23, 2026

Facile Preparation of Ultrafine Aluminum Hydroxide Particles with or without Mesoporous MCM-41 in Ambient Environments
Published on: May 11, 2017
Adsorption and thermodynamic properties of the alumina-polyacrylic acid solution system
M Wiśniewska1, S Chibowski, T Urban
1Department of Radiochemistry and Colloids Chemistry, Faculty of Chemistry, Maria Curie Sklodowska University, M. Curie Sklodowska Sq. 3, 20-031 Lublin, Poland. wisniewska@hektor.umcs.lublin.pl
Abstract:
Free energies of polyacrylic acid (PAA) adsorption (DeltaG( composite function)) on an alumina (Al(2)O(3)) surface in the temperature range 15-35 degrees C were estimated on the basis of adsorption-desorption measurements of the inorganic radioactive ions (36)Cl, (45)Ca, and (55)Fe. Adsorbing polymer macromolecules caused the desorption process of previously adsorbed radioactive ions. The free energy of Ca-PAA surface complex formation (DeltaG(o)) was estimated to be close to the free energy of Ca(2+) ions adsorption (polymer causes about 50% desorption of these ions). Moreover, a free energy of polymer molecule adsorption increase with the increasing temperature was observed. The obtained values of DeltaG(o) were compared with those calculated from the adsorption data. Additionally, the amount of polymer adsorbed and the thicknesses of polymer adsorption layers were determined in the temperature range 15-35 degrees C. The changes of polymer chain conformation with the temperature increase are responsible for the increase of PAA adsorption as well as thickness of polymer adsorption layers in the studied temperature range.
More Related Videos
Related Concept Videos
Composition of Polyprotic Acid Solutions as a Function of pH
A graph with the alpha values is plotted against the volume of base added during titration. Here, a...
Acid-Catalyzed Hydration of Alkenes
Solution Composition During Acid/Base Titrations
The α0 and α1 values represent the...
Basicity of Aliphatic Amines
To measure the basicity of amines, two conventions are generally used. The first defines Kb as the basicity constant for the deprotonation reaction of water by the amine, as presented in Figure 1. Conventionally, lower Kb indicates higher...
Physical Properties of Carboxylic Acids
Acidity of 1-Alkynes
The acidic strength of hydrocarbons follows the order: Alkynes > Alkenes > Alkanes. The strength of an acid is commonly expressed in units of pKa — the lower the pKa, the stronger the acid. Among the hydrocarbons, terminal alkynes have lower pKa values and are, therefore, more acidic. For example, the pKa values for ethane, ethene, and acetylene are 51, 44, and 25, respectively, as shown here.

