Reaction with Halogens, Acids, and Alkalis

Like the alkali metals, some halogens, particularly fluorine, form intercalated compounds with graphite crystals. Reaction usually starts at 600°C. However, graphite does not react with chlorine at temperatures below that of the electric arc. 

Oxidizing acids attack graphite to varying degree depending on the nature and surface area of the material. The reaction with concentrated nitric acid is as follows  

Depending on the reaction conditions, other products may be formed such as graphitic oxide (C7H2O4), mellitic acid (Ce(C02H)e) and hydrocyanic acid (HCN).f  

Another oxidizing acid that attacks graphite is boiling sulfuric acid. The simplified reaction is the following  

Other by-products may be formed such as benzoic acid, CgH5C02H, and mellitic acid, C6(C02H)6. 

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