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(Please show method and all work in latex for readability. Test is tomorrow) 1.

ID: 896318 • Letter: #

Question


(Please show method and all work in latex for readability. Test is tomorrow)

1. a) The attractive forces between molecules of a substance and their container is called_______________. The temperature where all three phases of a substance are is equilibrium is called the ______________ point. Raoult?s law involves a relationship between the mole fraction and the ______________ of the gas in a solution. The abbreviation for the concentration unit of the ratio of solute mass to solution mass times one billion is _________. When the temperature increases most gases become _______ soluble in solution.

b) Methanol, C3OH, has specific heat of 0.328 cal/g °C for its vapor and its heat of vaporization is 35.21 kJ/mole at its boiling point of 64.60 °C. Calculate the specific heat in J/g °C of liquid methanol if 122.1 kJ of heat is required to convert 100.0 g of liquid methanol at 32.60 °C to vapor at 95.60 °C. At wts:

C=12.00 g/mol, H=1.008 g/mol and O= 16.00 g/mol and

1cal=4.1840 J.

Ans = _______________

c) (6 points) Use the pertinent data from part b above and the Clausius-Clapeyron equation

the vapor pressure in Torr at 32.60 C. R=8.314

J/mol.K Hint: You need to use 273.2

Explanation / Answer

a) Adhesive forces , triplepoint , Relativelowering of vapour pressure , PPB , Insoluble.

b)

Qabsorbed = mliquid*s*DT + n*DHvap + mvapour*s*DT

122.1*10^3 = 100*sliquid*(64.6-35.21)+(100/32*35.21)+(100*0.328*4.18*(95.6-64.6)

sliquid = specific heat of liquid methanol = 40.06 j/g.c


2) DTf = i*Kf*m

DTf = (0-Tsolution)

i = 3*95/100 = 2.85

Kf = 1.86

m = (14/148.3)*(1000/100) = 0.944 molal

(0-Tsolution) = 2.85*1.86*0.944

tSOL = FREEZING POINT OF SOLUTION = -5.0044 c


b) PARTIAL pressure of O2 = 0.2095*0.75 = 0.157125 atm

C = k*P

C = 2.18*10^(-3)*0.157125 = 0.0003425 M