Figure 1From: Activity of zero-valent sulfur in sulfidic natural watersRelationship of a S 0 to ratios of polysulfide ion concentrations. The hatched region demarks aS0 values that are unattainable, except transiently, because rapid precipitation of inorganic colloids occurs. The curves are independent of pH provided pH is high enough that polysulfide ions are not appreciably protonated.Back to article page