Final answer:
The final reaction for glass ionomer is an acid-base reaction between fluoroaluminosilicate glass and polyacrylic acid, resulting in the release of ions and the setting of the cement. Hydrolysis of fluoride ions creates a slightly basic solution, and the setting occurs similarly to the conversion of isopropyl alcohol to acetone.
Step-by-step explanation:
The final reaction for glass ionomer involves a series of reactions culminating in the setting of the glass ionomer cement typically used in dentistry. The main components are a fluoroaluminosilicate glass and an aqueous solution of polyacrylic acid. The reaction begins with the acid-base reaction between the glass powder and the polyacrylic acid, leading to the release of calcium and fluoride ions. The fluoride ions then undergo hydrolysis, which slightly increases the pH of the setting material, making the solution slightly basic. Silicon dioxide (SiO₂), a common component in glass production, behaves as a Lewis acid in these reactions, reacting with the Lewis base in the matrix. Finally, in a similar manner to the conversion of isopropyl alcohol to acetone, this polyacrylic acid matrix hardens, thus setting the glass ionomer.
Additionally, in explaining the reaction for creating glass, Si(s) + 2MgO(s) → SiO₂(s) + 2Mg(g), Le Châtelier's principle is employed to remove the magnesium vapor, which in turn drives the reaction forward despite its thermodynamic unfavorability. This principle is imperative in understanding how over 75% of the world's production of magnesium is managed through such reactions.