Asolution of sodium chloride in water has a vapor pressure of 19.6 torr at 25°c. what is the mole fraction of nacl in this solution? the vapor pressure of pure water is 23.8 torr at 25°c.

Mole fraction of Nacl is 0.173

Explanation:

we know that

where,

P sol  - the vapor pressure of the solution

χ  solvent - the mole fraction of the solvent

P ∘ solvent  - the vapor pressure of the pure solvent

This means that in order to be able to calculate the mole fraction of sodium chloride, you need to know what the vapor pressure of pure water is at  

25 ° C  You can use an online calculator to find that the vapor pressure of pure water at  25 C  is equal to about  23.8 torr .

=0.827

Also we know that

This means that the mole fraction of sodium chloride is

χ_{Nacl}= 1-Χ_{water}

= 1-0.827 =0.173

c (diamond),

sio2 (quartz)

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.