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A pure substance can be an element , which consists of only one type of atom and can not be broken down by a chemical change , or a compound , which consists of two or more types of atoms . The characteristics that enable us to distinguish one substance from another are called properties . A physical property is a characteristic of matter that is not associated with a change in its chemical composition . Familiar examples of physical properties include density , color , hardness , melting and boiling points , and electrical conductivity . We can observe some physical properties , such as density and color , without changing the physical state of the matter observed .
Please check all the words that can be used instead of the target word in the same context. Note that the morphology of the target (third person singular, past tense etc.) is considered to be applied to the candidate automatically in the process of paraphrasing.