Suggest how you would determine that the distillate collected is a pure substance

Distillation is a technique used to separate pure liquids from a mixture of liquids by boiling the mixture to the respective boiling points of the components and selective condensation. The pure liquid separated out after the condensation of vapors is called distillate. The distillate collected is expected to be pure. The purity of the distillate can be measured by recording the boiling point of that liquid. For example, if we have water separated out it should boil at 100 otherwise it can be treated as impure.