Question

What do we mean by the term `"mole fraction"`, with respect to a solution?

Answer 1

Well the mole fraction, `chi`, of a component in solution.....

Explanation:

...is given by the quotient.....

`chi_"component"="moles of component"/"total moles of solute and solvent that comprise the solution"`

And as an example, we could dissolve `58.44*g` of sodium chloride in `1*L` of water to get near enuff to a `1*mol*L^-1` solution. (The volume would change negligibly upon dissolution.

And thus `chi_"sodium chloride"=((58.44*g)/(58.44*g*mol^-1))/((1000*g)/(18.01*g*mol^-1)+(58.44*g)/(58.44*g*mol^-1))`

`=0.0177`

But in a binary solution, `chi_"solute"+chi_"solvent"=1` by necessity.

And so `chi_"solvent"=1-chi_"NaCl"=0.982`...