Liquids that dissolve completely in one another in any proportions is said to be miscible liquids whereas liquids that are not soluble in each other are said to be immiscible liquids.
Mixtures in which the components that make up mixture are uniformly distributed throughout the mixture are known as homogeneous mixtures whereas a mixture in which the components of the mixture are not uniform are known as heterogeneous mixture.
Thus, the correct match is:
1. a substance maintaining a uniform appearance throughout: homogeneous.
2. a mixture consisting of visibly different substances or phases: heterogeneous.
3. two liquids that will not mix with one another: immiscible.
4. the ability of liquids to be mixed together: miscible.
