Which of these mixtures would best be separated through distillation
dry ice and ice
soil and water
water and acetone
iron and sand

Water and acetone

Explanation: you will find that the water and the soil are polar opposite, while the principal component of the water are Hydrogen and Oxygen, in the acetone you will find a change of carbon, the components from each molecule confer to each one specific physical properties for example the boiling point, and the distillation is a physical separation based on the boiling point.

then you can find the boiling point of the water in 100 °C, and the boiling point of the acetone is 56 °C, this give as a difference of 44 °C,

then while the acetone is boiling the water is liquid state, and this give us the opportunity to the separate the acetone in gas state by condensation after the boiling.

a  solution  is always transparent, light passes through with no scattering from solute particles which are molecule in size. the  solution  is homogeneous and does not settle out. a colloid is intermediate between asolution  and a  suspension. while asuspension  will separate out a colloid will not.