Question

why solution are ideal at low temperature

Answer 1

In chemistry, an ideal solution or ideal mixture is a solution with thermodynamic properties analogous to those of a mixture of ideal gases. The enthalpy of mixing is zero[1] as is the volume change on mixing by definition; the closer to zero the enthalpy of mixing is, the more "ideal" the behavior of the solution becomes. The vapor pressure of the solution obeys Raoult's law, and the activity coefficient of each component (which measures deviation from ideality) is equal to one.[2]The concept of an ideal solution is fundamental to chemical thermodynamics and its applications, such as the use of colligative properties.

Answer 2

as solid will become more hard  to experiment on