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1. Gas Laws

   Advanced Problem Solving
2. Reactions: Single Gas Product Suppose that 200.0 mL of propane gas C3H8 at 1.00 atm and 298K is mixed with 1.00 L of oxygen gas at the same pressure and temperature and burned to form carbon dioxide gas and liquid water. Determine the final volume of the reaction mixture at 1.00 atm and 298 K if the reaction goes to completion. (note: volume of liquid water is negligible). Hint1: Write out the equation and balance it. Balance Carbons and Hydrogens first then oxygens. Hint 2: Check for any limiting reagents, which may leave some gaseous reactant unreacted. Hint 3: Find how much of each gas species is present. (many ways to do this, easiest is to recognize proportionality)
3. Reactions: Hint1: Write out the equation and balance. Hint 2: Check for any limiting reagents, which may leave some gaseous reactant unreacted. Hint 3: Find how much of each gas species is present. (many ways to do this, easiest is to recognize proportionality) Suppose that 200.0 mL of propane gas C3H8 at 1.00 atm and 298K is mixed with 1.00 L of oxygen gas at the same pressure and temperature and burned to form carbon dioxide gas and liquid water. Determine the final volume of the reaction mixture at 2.00 atm and 298 K if the reaction goes to completion. (note: volume of liquid water is negligible).
4. Reactions: Suppose that 200.0 mL of propane gas C3H8 at 1.00 atm and 298K is mixed with 1.00 L of oxygen gas at the same pressure and temperature and burned to form carbon dioxide gas and liquid water. Determine the final volume of the reaction mixture at 2.00 atm and 298 K if the reaction goes to completion. (note: volume of liquid water is negligible).
5. Reactions:Multiple Gas Product The reaction of solid dimethylhydrazine, (CH3)2N2H2, and liquefied dinitrogentetraoxide, has been investigated as a rocket fuel; the reaction produces gaseous carbon dioxide, nitrogen and water vapor, which are ejected as exhaust gases. In a controlled experiment solid dimethylhydrazine reacted with excess nitrogen tetroxide with a final pressure of 2.50 atm, with a temperature of 400.0K. Find the pressure of each gas. Hint: Write out and balance the equation. Hint2: If you know the ratios of products and all are at the same volume and temperature, what do you think must be true of their pressures in relation to each other? Hint3: what is the total pressure? What are the mol ratios of products? H2O+CO2+N2=2.5 atm H2O N2 CO2
6. Reactions: What is the coefficient on the N2O4? A) 1 B) 2 C) 3 D) 4 E) I don’t know The reaction of solid dimethylhydrazine, (CH3)2N2H2, and liquefied dinitrogentetraoxide, has been investigated as a rocket fuel; the reaction produces gaseous carbon dioxide, nitrogen and water vapor, which are ejected as exhaust gases. In a controlled experiment solid dimethylhydrazine reacted with excess nitrogen tetroxide with a final pressure of 2.50 atm, with a temperature of 400.0K. Find the pressure of each gas. Hint: Write out and balance the equation. Balance Carbons and Hydrogens First (coming from and going to one species each so its easiest), then you can do oxygens then nitrogens. Hint2: You now know the mole ratios of the products, and all are at the same temperature, what do you think must be true of the ratio of the gases pressures? Remember n∝P They must equal the mole ratios coefficients: 4 H2O: 2 CO2: 3N2 Hint3: What is the total pressure? What are the mol ratios of products? . H2O N2 CO2
7. Reactions: The reaction of solid dimethylhydrazine, (CH3)2N2H2, and liquefied dinitrogentetraoxide, has been investigated as a rocket fuel; the reaction produces gaseous carbon dioxide, nitrogen and water vapor, which are ejected as exhaust gases. In a controlled experiment solid dimethylhydrazine reacted with excess nitrogen tetroxide with a final pressure of 2.50 atm, with a temperature of 400.0K. Find the pressure of each gas. Hint: Write out and balance the equation. Hint2: what do you think must be true of the ratio of the gases pressures? Remember n∝P They must equal the mole ratios coefficients: 4 H2O: 2 CO2: 3N2 Hint3: What is the total pressure? What are the mol ratios of products? H2O=4/9(2.50 atm)=1.11atm CO2=2/9(2.50 atm)=0.556 atm N2=3/9(2.50atm)=0.834 atm H2O How are you doing? Got it, lets move on More time please Help!!!!! (don’t forget to raise your hand so we come over too.) N2 CO2
8. More reactions:(I’m not sure we’ll make it to this one, if we don’t the answer will be posted online) Hint 1: (a)“reacts completely” in this question means no limiting reagent, everything reacts all the way to zero. A 1.00 L sample of chlorine gas at 1.00 atm and 298 K reacts completely with 1.00 L of nitrogen gas and 2.00 L of oxygen gas at the same temperature and pressure. There is a single gaseous product, which fills a 2.00L flask at 1.00 atm and 298 K. Use this information to determine the following characteristics of the product. A) its emperical formula, B) its molecular formula, C) the most favorable Lewis structure based on formal charge arguments (the central atom is an N atom); d) the molecular shape. We need to get g/molto find the molecular mass and therefore the molecular formula. Total g=total grams put in, total moles=can be found from ideal gas law of final reaction flask. We’ll then compare this to the empirical mass (aka mass of NClO2) Hint 2: (a) Remember V ∝ n at constant pressure. Also don’t forget the reactants are diatomic gases. Total Mass put in the following for each reactant species: Hint 3: (b) You know P, V, T of the final reaction flask, what is n?, what mass of reactants were put in? Where did all those reactants go. What is the units of molecular mass? Total moles: use ideal gas law for final reaction flask.
9. More reactions:(I’m not sure we’ll make it to this one, if we don’t the answer will be posted online) A 1.00 L sample of chlorine gas at 1.00 atm and 298 K reacts completely with 1.00 L of nitrogen gas and 2.00 L of oxygen gas at the same temperature and pressure. There is a single gaseous product, which fills a 2.00L flask at 1.00 atm and 298 K. Use this information to determine the following characteristics of the product. A) its emperical formula, B) its molecular formula, C) the most favorable Lewis structure based on formal charge arguments (the central atom is an N atom); d) the molecular shape. Hint 2: (a) Remember V ∝ n at constant pressure. Also don’t forget the reactants are diatomic gases. Total Mass Put in: Hint 3: (b) You know P, V, T of the final reaction flask, what is n?, what mass of reactants were put in? Where did all those reactants go. What is the units of molecular mass?
10. More reactions:(I’m not sure we’ll make it to this one, if we don’t the answer will be posted online) Ratio of gas moles=ratio of gas volume: 1Cl2:1N2:2O2 A 1.00 L sample of chlorine gas at 1.00 atm and 298 K reacts completely with 1.00 L of nitrogen gas and 2.00 L of oxygen gas at the same temperature and pressure. There is a single gaseous product, which fills a 2.00L flask at 1.00 atm and 298 K. Use this information to determine the following characteristics of the product. A) its emperical formula, B) its molecular formula, C) the most favorable Lewis structure based on formal charge arguments (the central atom is an N atom); d) the molecular shape. Hint 2: (a) Remember V ∝ n at constant pressure. Also don’t forget the reactants are diatomic gases. Total Mass Put in: Total Moles reactant: Hint 3: (b) You know P, V, T of the final reaction flask, what is n?, what mass of reactants were put in? Where did all those reactants go. What is the units of molecular mass?
11. More reactions:(I’m not sure we’ll make it to this one, if we don’t the answer will be posted online) A 1.00 L sample of chlorine gas at 1.00 atm and 298 K reacts completely with 1.00 L of nitrogen gas and 2.00 L of oxygen gas at the same temperature and pressure. There is a single gaseous product, which fills a 2.00L flask at 1.00 atm and 298 K. Use this information to determine the following characteristics of the product. A) its emperical formula, B) its molecular formula, C) the most favorable Lewis structure based on formal charge arguments (the central atom is an N atom); d) the molecular shape. Why can’t we add another double bond to minimize formal charge further?