The correct answer is option 1, Potassium permanganate.

Water of crystallization refers to water molecules that are attached to the crystal lattice structure of a salt. In certain salts, water molecules are incorporated into the crystal structure, making them part of the compound. These water molecules are called water of crystallization.

Option 1, Potassium permanganate, does not possess water of crystallization. Potassium permanganate is a compound with the chemical formula KMnO4. It is an ionic compound where the potassium (K+) and permanganate (MnO4-) ions are held together by ionic bonds. Potassium permanganate does not contain any water molecules incorporated into its crystal lattice structure, so it does not possess water of crystallization.

On the other hand, options 2, 3, and 4 possess water of crystallization. Blue vitriol (option 2) is also known as copper sulphate pentahydrate (CuSO4·5H2O), which means it contains five water molecules in its crystal structure. Washing soda (option 3) is the common name for sodium carbonate decahydrate (Na2CO3·10H2O), which means it