Direct Evidence for the Low Reactivity Towards Oxygen of Elemental Carbon

Graphite flakes were examined in a microcalorimeter and zero results obtained at the operating temperatures, signifying very low reactivity. Other materials including sawdust and coal were examined in the instrument in similar quantities, with positive results. A semi-quantitative calculation was performed to deduce at what temperature the graphite would give a positive sig nal, and this was shown to be 50-60° above the operating range of the instru ment.