Formation of a solution from two componenets can be considered as :
(i) pure sovent `rarr` separated solvent molecules, `/_\H_(1)`
(ii) Pure solute `rarr`separated molecules,`/_\H_(2)`
(iii) separated sovent and solute molecules`rarr`solution, `/_\H_(3)`
solution so formed will be ideal if :

Options

A. `Delta H_("soln") = DeltaH_3-DeltaH_1-DeltaH_2`
B. `DeltaH_("soln") = DeltaH_1 + DeltaH_2 + DeltaH_3`
C. `DeltaH_("soln") = DeltaH_1 + DeltaH_2 - DeltaH_3`
D. `DeltaH_("soln") = DeltaH_1 - DeltaH_2 - DeltaH_3`

Answer

B

Explanation

For an ideal solutio, `DeltaH_("mixing")=0`
`DeltaH = DeltaH_1 + DeltaH_2 + DeltaH_3` (According to Hess.s law)
i.e., for ideal solutions, there is no change in magnitude of the attractive forces in the two components present.