Reaction of Metal Chloride With Concentrated Sulphuric Acid:

Any metal chlorides react with concentrated sulphuric acid to give Hydrochloric acid and Sodium hydrogen sulphate.

e.g.    NaCl (s)      +      H2SO4 (l)            →          HCl (g)      +       NaHSO4 (s)

                                    (concentrated)

HCl that is produced cannot reduce H₂SO₄ Acid any further:

HCl (g)         +            H₂SO₄ (l)             →     No reaction

Observation : Misty/ Steamy Fumes Due to the formation of HCl gas because HCl gas is extremely soluble in water vapour in the air.