Does the concentration of concentrated sulfuric acid decrease or increase when heated?
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The boiling point of 98% concentrated sulfuric acid is over 300°C. Does the concentration decrease or increase after heating the concentrated sulfuric acid? Theory 1, the water evaporates, and the concentration increases. Theory 2, the solute sulfur trioxide volatilizes, and the concentration decreases (for example, 30% concentrated hydrochloric acid becomes 20% constant boiling point acid after heating). These two are contradictory, which one is correct?
I added 3% mass fraction of hydrogen peroxide for treatment.
98 acid is already an azeotrope. It is heated to vaporize and then heated to crack. In fact, the concentration is neither high nor low.
The water evaporates and the concentration increases. When the concentration increases to 98.3%, it becomes an azeotropic gas and liquid phase with the same concentration.