Pure substances are in appearance

The Pure substances are Homogenous in appearance

A pure substance ( a homogenous mixture ) appears in uniformity. i.e. all sides of a pure substance regardless of the size of the substance will appear in the same color or texture when observed. some examples of pure substances are ; pure water and steel.     while

An Impure substance is a non-homogenous mixture whereby some parts of the substances will appear in different colors or texture when put under observation.

Hence we can conclude that pure substances are Homogenous in appearance.

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h let me think

radioactive decay occurs in unstable atomic nuclei – that is, ones that don't have enough binding energy to hold

the nucleus together due to an excess of either protons or neutrons.