<p> Unit 6 Challenge Questions</p><p>1. The surface temperature of Venus is about 1050 K, and the pressure is about 75 earth atmospheres. Assuming these conditions represent a Venus “STP”, what is the standard molar volume (in liters) of a gas on Venus?</p><p>2. Assume that you take a flask, evacuate it to remove all the air, and find its mass to be 478.1 g. You then fill the flask with argon to a pressure of 2.15 atm and reweigh it. What would the balance read (in grams) if the flask has a volume of 7.35 L and the temperature is 20.0 C?</p><p>3. What is the total mass (in grams) of oxygen in a room measuring 4.0 m by 5.0 m by 2.5 m? Assume that the gas is at STP and that the air contains 20.95% oxygen by volume.</p><p>4. Chemical explosions are characterized by the instantaneous release of large quantities of hot gases, which set up a shock wave of enormous pressure (up to 700,000 atm) and velocity (up to 20,000 mi/hr). For example, explosion of nitroglycerin (C3H5N3O9) releases four gases, A, B, C, and D:</p><p>C3H5N3O9 (l)  a A (g) + b B (g) + c C (g) + d D (g) Assume that the explosion of 1 mol (227 g) of nitroglycerin releases gases with a temperature of 1950 C and a volume of 1323 L at 1.00 atm of pressure. a) How many moles of hot gas are released by explosion of 0.00400 mol of nitroglycerin?</p><p> b) When the products released by an explosion of 0.00400 mol of nitroglycerin were placed in a 500.0 ml flask and the flask was cooled to -10 C, product A solidified, and the pressure inside the flask was 623 mm Hg. How many moles of A were present, and what is its likely identity?</p><p> c) When gases B, C, and D were passed through a tube of powdered Li2O, gas B reacted to form Li2CO3. The remaining gases, C and D, were collected in another 500.0 mL flask and found to have a pressure of 260 mm Hg at 25 C. How many moles of B were present, and what is the likely identity?</p><p> d) When gases C and D were passed through a hot tube of powdered copper, gas C reacted to form CuO. The remaining gas, D, was collected in a third 500.0 mL flask and found to have a mass of 0.168 g and a pressure of 223 mm Hg at 25C. How many moles of C and D are present, and what are their likely identities? e) Write a balanced chemical equation for the explosion of nitroglycerin.</p>