Question

Ayudaaaa porfavooor

Answer 1

4.

Δtc = K. m

m = mol /Kg svte        m = masa sto /Mm Kg svte

1. calcular Δtc = 4.5 ºC - 5.5 ºC = -1 ºC

Tc = OºC - (-1)ºC = 1 ºC

Δtc = Kc · masa sto              despejar Mm
                 ````````````````
                   Mm · Ksvte

Mm = Kc . masa sto
                   ``````````````
                   Δtc · Kg svte

Mm = 5.12 ºC· m · 2.0 g
           ``````````````````````````
          1 ºC · 0.050 Kg svte

Mm = 204.8 g/mol ≈ 205 g/mol

5.
π · V = n · R  · T      ;    M = n/V

π =  n  · R  ·  T      susituir n/v
     ``````
         V

π = M · R · T

M = 0.010
R = 0.0821 (L · atm / mol · K)
T = 20 ºC + 273 = 293 K
π = 0.010 mol/L  · (0.0821 L · atm / mol · K) · 293 K
π = 0.240 atm.

6.
calcular mol

mol metanol = 50 g / 32 g/mol = 1.56 mol
mol etanol = 250 g / 46 g/mol = 5.43 mol

moles totales = ( 1.56 + 5.43) mol = 6.99 mol

calcular fraccion molar del soluto y solvente

Xsoluto =    1.56 mol
                 ``````````````````
                     6.99 mol

X sto = 0.223

X svte =    5.43 mol
               ``````````````````
                   6.99 mol

Xsvte = 0.776

3. calcular presion de vapor

P metanol = 95 mmHg ·  0.223 = 21.19 mmHg
P etanol  =  45 mmHg  ·  0.776 = 34.92 mmHg
P total = 21.19 mmHg + 34.92 mmHg = 56.11 mmHg