What does being an "elementary substance" mean?


> 
> Which of the following isn't an elementary substance?
> 
> 
> 1. Ozone
> 2. Sulfur
> 3. diamond
> 4. quartz
> 
> 
> 


I don't get what **elementary substance** means.


By seeing the options and the word elementary, I guess it means something like pure or obtained in its original form.




From [LATINTOS](http://golatintos.blogspot.com/2013/03/a-term-in-chemistry-elementary-substance.html):



> 
> An elementary substance is a pure chemical substance that consists of atoms belonging to a single chemical element. 
> 
> 
> 


Now you should be able to solve your question.


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