part of has part derives from output of formed as result of sulfur molecular entity sulfur oxide volcanic eruption fog vog "Vog and smog are different. Vog is formed when sulfur oxides emitted by a volcano react with moisture to form an aerosol. The aerosol scatters light, thus making the vog visible. Smog is formed largely from the incomplete combustion of fuel, reacting with nitrogen oxides and ozone produced from carbon monoxide by reactions with sunlight. The result is also a visible aerosol." A fog which is composed of liquid aerosols and gases derived from volcanic gas emissions (primarily sulfur oxides), formed when sulfur-bearing gases react with sunlight, oxygen, and moisture in an atmosphere. gas emission process