Here's why:

* Solubility Rules: In general, phosphates (PO₄³⁻) are insoluble in water, except for those with Group 1 cations (like Na⁺, K⁺) and ammonium (NH₄⁺).

* Ionic Compounds: Iron phosphate is an ionic compound, meaning it is formed by the electrostatic attraction between iron (Fe³⁺) and phosphate (PO₄³⁻) ions. The strong attraction between these ions makes it difficult for them to dissociate in water.

Therefore, iron phosphate will not dissolve significantly in water.