the following reaction 2NO2g N2O4g Suppose 152 g of nitrogen dioxide NO 2 is

# The following reaction 2no2g n2o4g suppose 152 g of

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)the following reaction: 2NO2(g) N2O4(g) Suppose 15.2 g of nitrogen dioxide (NO2) is placed in a 10.0 L flask at high temperature and then the flask is cooled to 25°C. The total pressure is measured to be 0.500 atm. What partial pressures and mole fractions of each are present?
37 Mother beautiful Partial Pressure Problem 2NO2(g) N 2 O 4 (g) Initially there is 15.2 g/46.01 g mol -1 = 0.330 mol of NO 2 and therefore the same number of moles of nitrogen atoms. If at 25°C there are n moles of NO 2 and n moles of N 2 O 4 then because the total number of moles of nitrogen atoms is a unchanged: n NO2 + 2n N2O4 = 0.330 mol
Mother beautiful Partial Pressure Problem
39 Mother beautiful Partial Pressure Problem Subtracting n NO2 + n N2O4 = 0.204 mol From n NO2 + 2n N2O4 = 0.330 mol n NO2 = 0.126 mol n N2O4 = 0.078 mol From these results, NO 2 has a mole fraction of 0.62 and a partial pressure of 0.62(0.50 atm) = 0.31 atm; N 2 O 4 has a mole fraction of 0.38 and a partial pressure of 0.38(0.50 atm) = 0.19 atm
40 Dalton’s Law of Partial Pressure All the early experiments were done using air a rather complex mixture of gases. The ideal gas law holds for this kind of mixture for two reasons: Gases mix homogeneously (they from solutions) in any proportions Each gas in the mixture behaves as if it were the only gas present ( No chemical interactions/reactions occur! ) Volume and temperature must be held constant.
41 Dalton’s Law John Dalton 1766-1844
Dalton’s Law of Partial Pressure: Dalton’s Law of Partial Pressure: The pressure of a gas mixture is the sum of the pressures of the individual gases. (P total = P A + P B) Why does each gas in a mixture contribute to the total pressure in proportion to its mole fraction?
43 Dalton’s Law of Partial Pressure: Dalton’s Law of Partial Pressure: The pressure of a gas mixture is the sum of the pressures of the individual gases. SLIDE 52 (P total = P A + P B) Why does each gas in a mixture contribute to the total pressure in proportion to its mole fraction?
44 Dalton’s Law of Partial Pressure: A mixture of gases contains 4.46 mol of neon, 0.74 mol of argon, and 2.15 mol xenon. Calculate the partial pressures of the gases the total pressure is 2.00 atm at a certain temperature. This question could be worded using grams or some other form making you calculate the number of moles.
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