2 The partial pressu atm a How many molecules of water are i

-2 The partial pressu atm. (a) How many molecules of water are in 3.98 cm3 of saturated air at 24 °c? molecules (b) What volume of saturated air at 24 °C contains 0.462 mol of water?

Solution

P   = 2.95*10^-2 atm   = 0.0295atm
T   = 24+273 = 297K
V    = 3.98cm^3   = 0.00398L
PV = nRT
n   = PV/RT
    = 0.0295*0.00398/0.0821*297   = 4.8*10^-6 moles
no of molecules = no of moles * 6.023*10^23
                 = 4.8*10^-6*6.023*10^23   = 2.89*10^18 molecules
b.PV =nRT
V = nRT/P
      = 0.462*0.0821*297/0.0295   = 381.87L

no of moles of CO2 = W/G.M.Wt
                     = 52.84/44   = 1.2 moles
T = 37+273 = 310K
V = 1.445L
a = 3.592atm l^2/mole^2
b = 4.267*10^-2 L/mole
PV = nRT
P   = nRT/V
    = 1.2*0.0821*310/1.445   = 21.13atm
(P+an^2/v^2)(v-nb) = nRT
(P+ 3.592*(1.2)^2/(1.445)^2) = 1.2*0.0821*310   = 28.06atm
attractive