Lowering of Vapour Pressure - a C.P ?

[zorro]

Is lowering of vapour pressure a colligative property?

I tried proving this and found it to be true.

P_a = P^o_aχ_a, where a=solvent and b=solute

Substituting χ_a=1-χ_b and some rearranging, we get

P^o_a-P_a=P^o_aχ_b

As P^o_a is constant for a given liquid at a given temperature, lowering of vapour pressure (LHS) is directly proportional to the no. of moles of solute provided the solution is very dilute.

Is my proof correct?

 

[wazani]

Hi
your proof is correct
right lowering of vapour pressure really is a colligative property

 

[zorro]

But my book says that Relative lowering of vapour pressure is a colligative property but lowering of vapour pressure is not a colligative property.

 

[asamaid1]

hi,

can anyone tell me where i can get a free reaction simulation software, like aspen plus.

thanks.

 

[LudusRex]

Yes, your proof is correct. Lowering of vapour pressure is indeed a colligative property, meaning it is dependent on the number of particles present in a solution rather than the identity of those particles. This is because the presence of solute particles reduces the number of solvent particles available to escape into the gas phase, resulting in a lower vapour pressure. Your equation accurately represents this relationship and your proof supports the concept of colligative properties. Well done!