6 (a) N₂Os decomposes in the gas phase by the reaction: 2 N₂Os (g) 4 NO₂ (g) + O₂(g) At 25°C, a sample of gaseous N:Os showed the following dependence of concentration on time: Time/h 0 5 10 15 20 [N:O)/(mmol dm³) 8.0 4.3 2.3 1.20 0.64 Determine the order of reaction by plotting an appropriate graph Determine the rate constant for this reaction. Find the concentration of NO₂ after 25 h.

One half-cell in a voltaic cell is constructed from a copper wire electrode in a 4.0 x 10-8 M solution of Cu(NO3)2. The other half-cell consists of a zinc electrode in a 0.75 M solution of Zn(NO3)2. Calculate the cell potential. You may need to use the following data: Zn²+ (aq) + 2 e¯ + Zn(s) E° = -0.763 V Cu²+ (aq) + 2 e → Cu(s) E° = +0.337 V Potential =

8.2 L of chlorine gas at 298 K and 3.0 atm is added to a rigid 4.0 L reaction vessel containing 3.2 moles of He gas and 2.4 moles of fluorine gas?  Chlorine and Fluorine gas react according to the following reaction at 298 K.                                                               Cl2 (g)    +    3 F2  (g)    à 2 ClF3 (g)               What is the partial pressure of ClF3 after the reaction is complete?                If the reaction proceeded with a percent yield of 40%, what would be the partial pressure of ClF3?

Using the phase diagram here, at what temperature will a solution of 36 mole % A begin to boil? Temperature-Composition Phase Diagram for Compositions of Compounds A and B 500 450 400 350 300 250 200 150 100 50 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Composition (mole fraction B) Temperature (°C)

The balanced equation below is for the reaction of magnesium with hydrochloric acid: • Mg(s) + 2HCI(aq) – MgCl,(aq) + H;(g) This reaction can be used to produce hydrogen gas, which is flammable (can catch on fire). If you have 2 moles of pure magnesium (Mg), and 2 moles of hydrochloric acid (HCI), according to the equation which is the limiting reactant? Show your work and/or

29.2 Hydrogen sulfide (H₂S) is a common contaminant in natural gas. The dissolution of H₂S gas in water is a linear function of partial pressure, as is described by Henry's law of the form PA = H x. Values of H vs. temperature are provided below: T (°C) H (atm) mole H₂S/ mole MEA 20 483 PA (mm Hg) 30 449 Given the relatively low solubility of H₂S in water, an amine- based chelating agent is added to the water to improve the solubility of H₂S. Equilibrium distribution data for H₂S in a 15.9 wt% solution of monoethanolamine (MEA) in water at 40°C is provided below: 40 520 50 577 0.000 0.125 0.208 0.362 0.643 0.729 0.814 0.00 0.96 3.00 9.10 43.1 59.7 106 Describe the effect of temperature on the solubility of H₂S gas in water. b. Prepare equilibrium distribution plots, in mole-fraction coordinates (y₁ -— XÃ), for the solubility of H₂S in water vs. H₂S in 15.9 wt% MEA solution at 40°C and 1.0 atm total system pressure. Comment on the relative solubility of H₂S in water vs. MEA solution.

P2

Use the information about three gases, with the properties below to answer the following questions. Nitrogen (N2) Oxygen (02) Argon (Ar) 93.0 °C 83.0 °C 73.0 °C M (kg/kmol) 28 32 40 Use the van der Waals equation of state and mixing rules to calculate the temperature where 100 kmol of a mixture of argon (10 mol%), nitrogen (45 mol%) and oxygen (45 mol %) would occupy 46.27 m³, at a pressure of 6.28 MPa. It is known that the van der Waals constant for nitrogen are a=1.370 atm(m³/kmol)² and b=0.0387 m³/kmol, and for oxygen are a=1.382 atm(m³/kmol)² and b=0.03186 m³/kmol. 63.0 °C Tc (K) 126.2 154.6 150.8 Pc (atm) 33.5 49.8 48 @ 0.04 0.021 -0.004