The water molecules have the boiling point of 100°C or 212° Other substances have different boiling points.
If the water contains the oil drops they can be found also in the distillate. Anyway, theoretically, they will begin to evaporate. And now here’s the question. What’s happening in distillation process? Organic substances, that have similar boiling point than that of water can slip in the distilled water. To eliminate organic problem substances, the water distillers have pre and post water filters. Here’s a question. Basically the substance that boils at a lower temperature evaporates first. It is the substance that boils at a lower temperature evaporates first. So there’re practically no salts in the distilled water, since the salt boils at a much higher temperature. For instance, various boiling point impurities is higher, when the water has already boiled out. Theoretically after the distillation the absolutely pure water is obtained. Now let me tell you something. Notice that fact, since this difference the water is separated.