Presentation on theme: "Molecular Composition of Gases Stoichiometry of Gases."— Presentation transcript:
Molecular Composition of Gases Stoichiometry of Gases
Objectives 1.Apply the principles of stoichiometry to determine the volume of any gas that is produced or consumed in a chemical reaction.
Volume-Volume Calculations At STP, what volume of hydrogen gas is needed to react completely with 4.55 L of oxygen gas to produce water vapor? 2 H 2 + O 2 2 H 2 O
Stoichiometry of Gases 2 CO (g) + O 2 (g) 2 CO 2 (g) 2 molecules CO + 1 molecule O 2 2 molecules CO 2 2 mol CO + 1 mol O 2 2 moles CO 2 2 L CO + 1 L O 2 2 L CO 2
Volume-Volume Calculations Xenon gas reacts with fluorine gas to produce the gaseous compound xenon hexafluoride. If a researcher needs 3.14 L of xenon hexafluoride for an experiment, what volumes of xenon and fluorine should be reacted. Assume all volumes are measured under the same conditions of temperature and pressure. Xe + 3 F 2 XeF 6
Volume-Volume Calculations Nitric acid can be produced by the reaction of gaseous nitrogen dioxide with water. 3 NO 2 (g) + H 2 O (l) 2 HNO 3 (l) + NO (g) If 708 L of NO 2 gas react with water, what volume of NO gas will be produced? Assume the gases are measured under the same conditions.
Volume-Mass Calculations Aluminum granules are a component of some drain cleaners because they react with sodium hydroxide to release both heat and gas bubbles, which help clear the drain clog. The reaction is… 2 NaOH (aq) + 2 Al (s) + 6 H 2 O (l) 2 NaAl(OH) 4 (aq) + 3H 2 (g) What mass of aluminum would be needed to produce 4.00 L of hydrogen gas at STP?
Volume-Mass Calculations Air bags in cars are inflated by the sudden decomposition of sodium azide, NaN 3, by the following reaction: 2 NaN 3 (s) 3 N 2 (g) + 2 Na (s) What volume of N 2 gas, measured at 1.30 atm and 87 o C, would be produced by the reaction of 70.0 g of NaN 3 ?
Volume-Mass Calculations Rocket propulsion systems and some explosives employ reactions that suddenly produce a large volume of hot gas from a small volume of reactants. For example, the explosive substance, nitroglycerin undergoes the following decomposition reaction when detonated. 4 C 3 H 5 (ONO 2 ) 3 (l) 12 CO 2 (g) + 10 H 2 O (g) + 6 N 2 (g) + O 2(g) Calculate the total volume of gases produced by the reaction of 4 moles of nitroglycerin. (12 mol + 10 mol + 6 mol + 1 mol)(22.4 L / mol ) = 650. L