Question

mole fraction of a solute in 2.5m aqueos solution

Answer 1

let x is mole fraction and M is molar mass of solvent ,
molality =x.1000/(1-x)M
2.5 =1000x/(1-x)18
2.5 x 18 =1000x/(1-x)
45/1000 =x/(1-x)
0.045 =x/(1-x)
0.045 -0.045x =x
0.045 =1.045x
x =0.045/1.045
x =0.043