Asubstance that cannot be separated into other kinds of substances is a(n) .

A pure substance. Since the particles inside of it are uniformly spread throughout the mixture, it is impossible to split into other substances. 

Glucose, also called grape sugar, blood sugar or corn sugar, is among the simplest and one of the primary naturally occurring sugars. produced naturally by plants as the primary photosynthesis product, it is heavily used by living beings as a main energy source and is necessary for cellular respiration. chemically, it is a monosaccharide carbohydrate and serves as a building block for complex sugars like starch.