1. Assume that you are on a planet whose atmosphere does not contain carbon dioxide, only nitrogen, oxygen, and water vapor.

(a) What would be the pH of the rain at 298K?

(b) Lets assume the alien life on the planet lives by eating sulfur and producing sulfur dioxide. If the atmospheric reaches a concentration of 20.0 ppmv of SO₂ what would the pH of the rain be at 298K and 1 atm. Use K_H for SO₂ = 1.12 M/atm and K_a= 1.7x10^-2 molL^-1

2. (a) Calculate the volume (at 20°C and 1.00 atm) of SO₂ produced by conventional roasting of 9.561 tonnes (9561 kg) of copper sulfide ore, CuS.

(b) What volume (in liters) of pure sulfuric acid (d= 1.8305 g/cm³) could be produced from this amount of SO₂ if it were oxidized to SO₃ and then reacted with water?

(c) My previous research group has developed a patent-pending method for converting sulfur dioxide to sulfur and sulfuric acid:

24 SO₂+ 16 H₂O → S₈ + 16 H₂SO₂

How much sulfur and how much sulfuric acid (in Kg) can be produced from the SO₂ according to part (a) of this question.

(d) Look up the prices at Aldrich (either online or a recent chemical catalog) for sulfur and sulfuric acid (use prices for reagent grade material). Which process is more economical? Please show the pricing and your calculations in the answer.

3. (A) If all of the ice on the planet were to melt it would produce 2.8 x 10⁷ km³ of water. The surface area of the ocean is 3.61 x 10⁸ km². Assuming that all of the water piled up on the top of the ocean and did not spread out, how large would the increase in sea height be (in meters)?

(B) Besides the assumption that the water does not spread out, what other factors may make this calculation incorrect. Hint: Consider the polar ice caps and icebergs and elementary school physics.

4. The rate constant (k) for the reaction

XH + OH· → X· + H₂O

Is 4.28 x 10^-5 molecules^-1cm³s^-1. If the atmospheric concentration of concentration of OH· radical is 8.04 x 10¹² molecules cm^-3.

Calculate the half-life of XH.

5. If the concentration of atmospheric CO₂ were to double from its current level of 370 ppm, what would be the calculated pH of rainwater (assuming that CO₂ were the only acidic input)? With respect to rising CO₂ levels, do we have to be concerned about enhanced acidity of rain? See notes below for help with this calculation.

6. If the particle mass concentration on Hall of Fame in front of the construction area is 250 ug/m³, and the average particle size is 0.21 gm, what is the average number of particles/cc?? Assume a density of 0.98 g/ cm³ for the particles.

7. The rate constant for oxidation of nitric oxide by ozone is 2.4 x10^-14 cm³/molecule•s whereas that for the competing reaction where it is oxidized by oxygen is 2.3 x 10^-38 cm³/molecule•s

2 NO + O₂ → 2 NO₂

In a typical morning smog condition the concentration of ozone is 42 ppb and that of NO is 78 ppb. Deduce the rates of the two oxidation reactions. Which one is the dominant process?

8. Assuming the enthalpy and entropy of formation of NO are temperature independent, what temperature (in Celsius) would be required to generate 88 ppmv of NO from the reaction of nitrogen and oxygen? Hint: Use thermodynamic data calculate ΔG with a correction for non-standard conditions for N₂, O₂, and. NO. The reaction will become thermodynamically possible when ΔG = 0. Assume atmospheric pressure of exactly 1 atmosphere and normal atmospheric concentrations of nitrogen and oxygen.