Question

Calculate the partial pressure of O2 (P02, mm Hg) in dry air in Arcata (sea level-

assume atmospheric pressure of 760 mm Hg). Arcata air never gets fully dry.

Assume 90% humidity at 15°C (saturated water vapor pressure at 15°C=12.8 mm Hg)

and calculated the actual partial pressure of O2 in Arcata air

Answer 1

111 Pagel As per the given date : Here we will use Dalton's law of partial press -ure. It states that the total pressure by a mixture of gases is equal to the sum of the partial pressure on each of the constituent galls. The partial pressure as deffned as the pressure each gas woulb exert if it alone occupied the volume of the mixture at the same temperature, - Total atmospheric pressure at sea level = 760 mm Hg - mole fraction of Oz in doy apr = 0.2093 particular pressure of water vappur Pn him?d? -fied air = 12.8 mm Hg. 1. Pair = Poz t PN 2 t Peopt... E Now Ale to Dalton's daw on partial pressure Por = (x02] x [Pairt / :X02= mole frac (-thom hoz = 60.2093) 1760) = 159.060 mm Hg 15 159.10 mmHg / M 1. SO 2093 Paio= Total Pressure to doy atm apy = 760 mm Ha OYUYYSUITSUAMILOIWWWOW a

i Por at arcate is 159.10 mm Hz page-2 Now for humid/wet apris The atmosphere contain water vapour, from which We have to sub straut water vapour pressure. 1. Pwet air = PAzot Port ... = 760 mm Hg e Proyar =) P day as = (Puet aro - Al2O) = (760-12.8) = 727.2 mmHgco Now , we will use 0 to find the Por - Poz=(x02) (Peday aft) = (0.2003) (747.2) = 156. 388 16 F 156.40 mm Hg7 in the humid ter Arcata air is 156.40 mmHg 2x please give positive vote.