Abstract
The author reports how experimental-type lectures for the local community are carried out in Gunma National College of Technology. While ordinary lectures for the local community have been held since 2002, we started the experimental-type lectures in 2004. In this paper, new experimental-type lectures on air-activated disposable hand warmers for elementary schoolchildren are reported.
Air-activated disposable hand warmers produce heat from the exothermic oxidation of iron when exposed to air. They contain cellulose, iron, water, activated carbon, vermiculite and salt. In order to check the principle, the activated carbon, sodium chloride solution and iron powder were mixed. Immediately, the temperature of mixture increased and reached at ca. 80℃. The reagents used in this investigation are harmless and investigation is relatively easy. Therefore, the air-activated disposable hand warmers are suitable for the theme of experimental-type lectures for elementary schoolchildren.
