Chlorine: Manganese Dioxide, Common Salt and Sulphuric Acid Heated

The second laboratory way in Thorpe's Dictionary (1912), also used on the large scale: heat manganese dioxide and common salt with sulphuric acid. 2NaCl + MnO2 + 2H2SO4 = Cl2 + Na2SO4 + MnSO4 + 2H2O. Chlorine cannot be breathed: it rapidly attacks the membranes. Fume hood, respirator. The picture: our diagram.