Problem: In the atmosphere, sulfur dioxide and nitrogen dioxide react with water to give sulfurous acid and nitric acid. This produces “acid rain” which has a pH below 7 and can dissolve limestone. Sulfur dioxide, SO2, acts as a diprotic acid in aqueous solution. At 25°C the acidity constants are:SO2 (aq) + 2H 2O (l) ⇋ HSO3– (aq) + H3O+ (aq)               K a1 = 1.54 x 10–2HSO3– (aq) + H2O (l) ⇋ SO32– (aq) + H3O+ (aq)              K a2 = 1.02 x 10–7Calculate the pH of the above solution.A. 8.4B. 13.2C. 1.32D. 1.81E. 0.84

We are being asked to calculate the pH of the solution if the concentration of sulfur dioxide in water saturated with sulfur dioxide is 1.5 M. 

We're going to calculate the pH of the solution using the following steps: 

Step 1: Construct an ICE chart for the equilibrium reaction.
Step 2: Write the K_a expression.
Step 3: Calculate for the equilibrium concentration.
Step 4: Calculate pH.

Step 1: Construct an ICE chart for the equilibrium reaction.

Since we’re dealing with a weak acid and K_a is an equilibrium expression, we will have to create an ICE chart to determine the equilibrium concentration of each species:

• SO₂ → weak acid → proton donor
• H₂O → will act as the weak base → proton acceptor

We will use the first equilibrium reaction given:

       SO₂ (aq) + 2H₂O (l) ⇋ HSO₃^– (aq) + H₃O⁺ (aq)               K_a1 = 1.54 x 10^–2