In picric acid is it necessary to mention phenol with double bond or not necesary?

It is not necessary to mention phenol with a double bond when referring to picric acid. Picric acid is also known as 2,4,6-trinitrophenol, and its chemical structure clearly indicates the presence of a phenol group with three nitro groups attached to it.

It is necessary to mention phenol with double bond in the structure of picric acid.

Picric acid is a chemical compound with the formula C6H2(NO2)3OH. It is a yellow, crystalline solid that is soluble in water and alcohol. Picric acid is a strong acid and a powerful oxidizing agent. It is used in the manufacture of explosives, dyes, and matches.

The structure of picric acid can be represented as follows:

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O2N-C6H2(NO2)3OH
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The double bond in the phenol ring is necessary to show the resonance structure of picric acid. Resonance structures are different Lewis structures that represent the same molecule. In the case of picric acid, the resonance structures show that the negative charge on the oxygen atom of the nitro group can be delocalized to the oxygen atoms of the phenol ring. This delocalization of charge makes picric acid a more stable molecule.