Abstract
The reaction between dried aluminum hydroxide gel (DAHG) and acid was represented by_??_where n is nearly zero is both cases of hydrochloric acid and nitric acid, and 0<η<1 in the case of sulfuric acid by thermal analysis.
2. In the reaction between DAHG and hydrochloric acid mixed with sulfuric acid or nitric acid mixed with sulfuric acid, the order of the reaction, n, changed remarkably at the ratio of about 5% sulfuric acid (in gram-equivalent) and the reaction velocity was minimum at this ratio.
3. The activation energy of the reaction between DAHG and acid was found to be about 20, 000 calories.
4. These facts mentioned above were in good agreement with the results of the pH measurement described in previous papers.
5. The heat of reaction, which agreed well with the values given in a critical table, was measured.
