S.P.L. Sgrensen not only introduced the p H concept, but in his classical paper from 1909 “Enzymstudien 11” he also described in great detail the colorimetric as well as the potentiometric methods for p H measurement, and he pointed out that two kinds of acidity must be distinguished: Actual acidity and titratable acidity. Previous to Sgrensen the acidity of a solution was usually determined by...

Acid or base concentrations can be determined by coulometric titration. A new alliridium oxide sensor-actuator device is presented, of which the titrant is generated by a reversible redox reaction occurring in the electroactive iridium oxide actuator electrode, and the equivalence point in the titration curve is detected by the pH-sensitive iridium oxide sensor. The advantage with respect to th...

Caries-associated biofilms induce loss of calcium from tooth surfaces in the presence of dietary carbohydrates. Exopolysaccharides (EPS) provide a matrix scaffold and an abundance of primary binding sites within biofilms. The role of EPS in binding calcium in cariogenic biofilms is only partially understood. Thus, the aim of the present study is to investigate the relationship between the calci...

Hypoventilation increases PaCO(2) (hypercapnia) and initiates the acid-base disorder known as respiratory acidosis. Hyperventilation decreases PaCO(2) (hypocapnia) and initiates the acid-base disorder known as respiratory alkalosis. The impact on acidity of these primary changes in PaCO(2) is ameliorated by secondary, directional changes in plasma bicarbonate concentration that occur in two sta...

Acid or base concentrations can be determined by performing an acid-base titration with OHor H+ ions, coulometricaliy generated by the electrolysis of water at a noble metal actuator electrode. This can be done very rapidly if the actuator electrode is in close proximity to an ISFET which is used as the indicator electrode to detect the equivalence point in the titration curve. In order to rest...

Several recent studies have made use of continuous acid-base titration data to describe the surface chemistry of bacterial cells as a basis for accurately modelling metal adsorption to bacteria and other biomaterials of potential industrial importance. These studies do not share a common protocol; rather they titrate in different pH ranges and they use different stability criteria to define equ...

Experiments are an important part of the chemistry curriculum. An indicator in form a synthesis is commonly used acid-base materials experiments. The usage synthetic indicators can result waste that both environmentally harmful and costly. butterfly pea flower one plants contains anthocyanins, which have potential to be as alternative indication natural acids bases. study aims determine acid ba...

Chemical equilibria, including acid-base play a significant role in the learning of general chemistry. Acid-base reactions as well acidity and basicity concepts their relationship to titrations are an important part any chemistry course, students have difficulties understanding these concepts. The purpose this research project is examine some challenges alternative conceptions that face about t...