Chemistry - Ideal Gas Question with Solution | TestHub
At room temperature, the following reaction goes to completion:
2 NO + O₂ 2 NO₂ N₂O₄
Dimer N₂O₄ at 262 K is solid. A 750 ml flask and a 250 ml flask are separated by a stop cock. At 300 K, the nitric oxide in the larger flask exerts a pressure of 2.4 atm and the smaller contains oxygen at 1.2 atm. The gases are mixed by opening the stop cock. After completion of the reaction, the flasks are cooled to 200 K. Neglect the vapour pressure of the dimer. (R = 0.08 l-atm/K-mol)
a = 1 (if the gas remaining at 200 K is NO) or 2 (if the gas remaining at 200 K is O₂) or 3 (if the gas remaining at 200 K is NO₂) or 4 (if the gas remaining at 200 K is N₂O₄)
bc = millimole of gas remaining at 200 K
d = 10 × the pressure (in atm) of gas remaining at 200 K.
The value of abcd is
Answer:
Solution:
n(NO) = 2.4 × 0.750/(0.08 × 300) = 75 mmol; n(O₂) = 1.2 × 0.250/(0.08 × 300) = 12.5 mmol.
2 NO + O₂ -> N₂O₄: 12.5 mmol O₂ consumes 25 mmol NO, leaving 50 mmol NO; the 12.5 mmol N₂O₄ formed solidifies at 200 K.
Gas remaining at 200 K is NO: a = 1, bc = 50.
P = nRT/V = 0.050 × 0.08 × 200/1.0 = 0.8 atm ⇒ d = 8.
abcd = 1508.
