Concentrated sulfuric acid – safe dilution, dehydrating and oxidizing properties

ChemistryInorganic ChemistryAges 16–17

Tab one: dilute 98% H₂SO₄ in two ways – pouring acid into water (correct: the temperature rises gradually, read on a thermometer and plotted against the volume of acid added) or pouring water into acid (wrong: the water floats on the acid, boils instantly and makes the acid spatter, with a warning). Tab two: concentrated H₂SO₄ chars sugar into a black, porous column of carbon and releases SO₂; hot concentrated H₂SO₄ oxidizes copper to CuSO₄ and SO₂, while dilute H₂SO₄ does not react with copper.