Which solution will shows the maximum vapour pressure at 300 K
a-1M C12H22O11
b-1M CH3COOH
c- 1M CaCl2
d- 1M NaCl

Dear student,

The vapour pressure of solution depends upon the number of solute particles present in the solution. More the number of solute particles lesser will be the vapour pressure. 
In above given solutions the concentration of all are same 1 M. Now, the vapour pressure depends on the dissociation of electrolytes. More is the  dissociation of electrolytes lesser will be vapour pressure. Out of these four NaCl and calcium chloride dissociates into ions, acetic acid is a weak electrolyte hence less dissociates.
Sucrose is a non electrolyte hence does not dissociates.
Therfore, Out of four, sucrose solution has highest vapour pressure.

Regards

  • 16
Pls find the answer below:

Vapour pressure depends of van toff factor i.e (i= 1+(n-1)x)
n=no.of moles
x=degree of dissociation

Greater the no. of moles greater will be the vapour pressure...

(a) & (b) are non-electrolyte the Vant hoff factor will be 1

In the case of C
aCl2 no. of moles will b 3 (Ca+ & 2cl-)

For Nacl its 2 , ( Na& cl-)

CONCLUSION:

Nacl will show the maximum VP


Hope it helps..!!!
  • -8
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