(A) Direct absorption of SO₃ in H₂O is commercially not possible
(R) Direct absorption of SO₃ in water forms a mist of corrosive vapours.

Statement A is true because direct absorption of SO₃ in water is not commercially feasible due to the highly exothermic nature of the reaction, which can lead to the formation of an aerosol or mist of sulfuric acid that can corrode the equipment used in the process. Therefore, indirect absorption is used in the Contact process, where SO₃ is first reacted with oleum (a mixture of sulfuric acid and sulfur trioxide) to form sulfuric acid, which is then diluted with water.

Statement R is also true because the direct absorption of SO₃ in water can indeed result in the formation of a mist of corrosive vapors. The reaction between SO₃ and water is highly exothermic and produces a fine mist of sulfuric acid droplets that can be carried away by air currents and cause corrosion in nearby equipment and infrastructure. This is one of the main reasons why indirect absorption of SO₃ is preferred in the Contact process.