Question

2. The air we breathe contains approximately 21.0 mol% oxygen. The average person breathes 0.50 L of air per breath a. If the atmospheric pressure is 745 mmHg, what is the partial pressure of oxygen in atmospheres? b. On a warm April day in Indiana, the air is 26.85 °C, how many moles of oxygen are inhaled in one breath? c. On top of Pikes Peak in Colorado, the temperature is -6.74 °C and the pressure is 442 mmHg. How many moles of oxygen are inhaled in one breath?

Answer 1

Ans. 2 21.0 mol % oxygen implics 21 mol of oxygen per loo mol of air. olume of air breathed per breathe = 0.50 L - Pressure = 745mming pastical presure = ? We know, p=xop pe partial pressure & mile fraction . 3 Xoxygen = x. 21 mol Pa total Pressure . Too mal Hoxygen = na noxygen oxygen = 0.21 o notal = p = 0.21 | 745 mming) latm=760mm Hg bartial = 156.45 mmiga presuse bartial pressure = 0.205 atm lans.) 156.45 mmng = 0.205 atm Ars-b Tempercituse - 26-85°C - 299.85k. (no of moles of the Moxygen = ? P = 745 mmHg = 745 atm = 0.98 atm Hence 760mmHg = Potom 1 a Iamm 160 (mongooled) top - 745 mong - V 760 Volume = 0.50l. Now, PV = nRT 0.98 ath x 0.508 = mx 0.0821 flash is mol-'x 299.85 K 0.98 xo.ro mol = n 0.0821 x 299.85 0.0199 m-1 n no. of moles of oxygen = 0.020 mol/ (Ans.) Temperature = -6.74°C = 2660 26k P = 442 mm Hg = 0.58 atm. r = o.solo PV = nRT 0.58 atfxo.sol = nx 0.0821 falfo ift molt x 266.26 x 000132 = n = noe Mules = 0.013 moles - =) • origen