1. Given the natural gas gravity to air Yg = 0.75, the pseudocritical pressure, PPC, and temperature, TPC are 667 psi and 405 R, respectively. If the pressure and temperature are 1,500 psi and 200F, respectively, calculate how many Ib of gas can fit in 1,000ft3 of space? At what pressure increase would the mass increase by 50%, if the temperature remains constant? 2. Calculation of gas reservoir volume. Use the real gas law to calculate the volume of 5 Ib-mol of a gas mixture at reservoir conditions of T = 1800F and p= 4,000 psi. Assume that this natural gas has the following molar composition: C₁ C₂ C3 i-C4 n-C4 i-Cs n-C5 n-C6 C7+ 0.874 0.083 0.022 0.006 0.002 0.008 0.003 0.001 0.001 C₁ 3. Calculate the Z-factor for a sour gas. Calculate the gas deviation factor, Z, of a sour gas at 1900F and 4,000 psi. Gas composition is given below. C₂ C3 i-C4 0.78 0.02 0.00 0.00 n-C4 i-Cs 0.00 0.00 4 8 7 08 05 08 03 5 n-C5 C6+ N₂ CO₂ H₂S 0.00 0.00 0.00 0.02 0.15 06 1 2 4. Relating downhole rate with the rate at standard conditions for a production rate of 10MMscf/d (million cubic feet per day), calculate the downhole rate if downhole p = 1,500 psi, T = 1800F, and gas gravity is 0.64(assume there are no non- hydrocarbon gases) 5. Calculate the initial gas-in-place, Gi. The reservoir is about 2,100 acres in area and 70 ft thick, reservoir porosity is 18%, and gas saturation Is 80%. Reservoir pressure and temperature are 4,000 psi and 1800f, respectively. The gas composition is the same as question 2. 6. Equations for the gas formation volume factor. Develop expressions for the gas formation volume factor and density in SI units, in terms of P, T and Z. Note: the standard conditions are: Psc =14.7 psia and Tsc = 520 R.