Consider the following diseases from which human beings are suffered.(I) Asthma                              (II) Dyspepsia(III) Bronchitis                         (IV) EmphysemaDiseases due to SO2 are

Even low concentration of SO2 causes respiratory diseases as asthma, bronchitis, emphysema in human beings. Note: Irritation in eyes is also due to SO2. Under high concentration of SO2, plants are affected and flowers fall off from plants. They are also decolourised due to reduction.SO2 + 2H2O → H2SO4Nascent [H] causes reduction and colour fades.