There are numerous chemical compounds and elements known to scientists, and they are still discovering new ones. However, not all chemical compounds or elements exist, and some have been proposed but have not been confirmed to exist. In this article, we will discuss non-existing species and provide examples.





PH3, also known as phosphine, is a chemical compound that exists. It is a colorless and flammable gas that is toxic and has a pungent odor. It is commonly used in the semiconductor industry and is also used as a fumigant in agriculture. Therefore, PH3 is not a non-existing species.



PH4 is a hypothetical compound that does not exist. It is a proposed compound that would be made up of phosphorus and four hydrogen atoms. However, scientists have not been able to synthesize it in a laboratory or find it in nature. Therefore, PH4 is a non-existing species.



[Pf6]^- is a chemical compound that does exist. It is a hexafluorophosphate anion that is commonly used as a counterion in coordination chemistry. It is a white crystalline powder that is soluble in water and has a high melting point. Therefore, [Pf6]^- is not a non-existing species.



In conclusion, not all chemical compounds or elements exist, and some have been proposed but have not been confirmed to exist. PH3 and [Pf6]^- are chemical compounds that exist, while PH4 is a hypothetical compound that does not exist.

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