CBSE Class 11-science Answered
Dear Student,
The sum of mole fractions of solute and solvent of a solution is unity or 1.
Explanation:
Mole fraction = Moles of solute or solution / Total moles of solution
If the solution contains n number of moles of solute and N number of moles of solvent, then the total moles of solution = n + N
Therefore,
Mole fraction of solute = n / n + N -------1
Where, n is the number of moles of solute and N is the moles of solvent.
Mole fraction of solvent = N / n + N ---------2
Where, n is the number of moles of solute and N is the moles of solvent
The sum of mole fractions of solute and solvent
= Mole fraction of solute +mole fraction of solvent
Substituting values from equations 1 and 2,
Sum of mole fraction of solute and solvent = (n / n + N) + (N / n + N) -------3
On solving 3,
The sum of mole fraction of solute and solvent = 1 = unity.