What gases escape from volcaneos

The principal components of volcanic gases are water vapor (H2O), carbon dioxide (CO2), sulfur either as sulfur dioxide (SO 2) (high-temperature volcanic gases) orhydrogen sulfide (H2S) (low-temperature volcanic gases), nitrogen, argon, helium, neon, methane, carbon monoxide and hydrogen.

Carbon dioxide, sulfur dioxide, hydrogen sulfide and hydrogen halidescarbon