Answer:
Step-by-step explanation:
Both elements and compounds are classified as pure substances. A pure substance is defined as a material that has a constant composition and fixed properties. Pure substances cannot be separated using physical separation techniques.
Elements are the simplest pure substances. They cannot be broken down or separated by any means, excluding nuclear fission and fusion. Most elements have been found naturally in the universe, most having been formed during the evolution of the universe, in the Big Bang. One example is iron (Fe), formed naturally during the fusion of stars.
Compounds are composed of elements in fixed atomic ratios and can be separated into component elements by chemical means. Examples include Silver bromide (AgBr), which can be separated into silver and bromine by photolytic decomposition (light); sodium chloride can be separated into sodium and chlorine by electrolytic decomposition (electricity); hydrochloric acid can be separated into chlorine upon reaction with water.