Answer:- Van't hoff factor(i) for the unknown ionic compound is 2.77.
Solution:- Elevation in boiling point is a colligative property and the equation used for solving this type of problems is...
delta Tb = i x m x kb
where delt Tb is elevation in boiling point.
i is Von't hoff factor.
m is molality of the solution and kb is the molal elevation constant. It's value for water is 0.512.
Boiling point of solution is given as 103.4 degree C and we know that water boils at 100 degree C.
So, delta Tb = 103.4 - 100 = 3.4 degree C
molality is given as 2.4m.
Let's plug in the values...
3.4 = i x 2.4 x 0.512
i = 3.4/(2.4 x 0.512)
i = 2.77