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The ionic compounds and the water molecules are polar in nature therefore both attract each other by the force of attraction.

Most ionic compounds dissociate and dissolve in water easily but if the force of attraction between ions of the ionic compound is stronger than the attraction force of water then its ionic bond does not dissociate and hence, these types of ionic compounds become water-insoluble.

Benzene,${\mathit{C}}_{\mathbf{6}}{\mathit{H}}_{\mathbf{6}}$ is insoluble in water because it does not have a polar hydrogen bond in its structure, hence it is a non-polar compound while water is a polar compound.

Sodium hydroxide is soluble because it is an ionic compound that dissociates into ions on dissolving in waterinto $\mathbf{}\mathit{N}{\mathit{a}}^{\mathbf{+}}$and $\mathit{O}{\mathit{H}}^{\mathbf{-}}$ions.

Ethanol,$\mathbf{\left(}{\mathbf{CH}}_{\mathbf{3}}{\mathbf{CH}}_{\mathbf{2}}\mathbf{OH}\mathbf{\right)}$ is soluble in water because it has a polar hydrogen bond in its structure.

Potassium acetate$\left(C{H}_{3}COOK\right)$ is soluble in water because it isan ionic compound, which will likely dissolve in water to form sodium ions and acetate ions that are held in solution through ion-dipole attractions to water.