Step 1: Define hydrolysis reaction.
Hydrolysis is a decomposition reaction in which a compound reacts with water ($ H_2O $) and is split by water molecules. In hydrolysis, water acts as a reactant and causes the breaking of chemical bonds in the substrate. The key feature: water is incorporated into the products by splitting its H and OH across a bond.
Step 2: Analyze option (1).
$ P_4O_{10} + 6H_2O \to 4H_3PO_4 $: Phosphorus pentoxide reacts with water, incorporating all water molecules into the phosphoric acid product. Water splits and adds across P-O bonds. This is hydrolysis.
Step 3: Analyze option (2).
$ Mg_3N_2 + 3H_2O \to 3Mg(OH)_2 + 2NH_3 $: Magnesium nitride reacts with water; $ N^{3-} $ accepts protons from water to form $ NH_3 $, and $ OH^- $ goes to $ Mg(OH)_2 $. Water is split and incorporated. This is hydrolysis.
Step 4: Analyze option (3).
$ SiCl_4 + 2H_2O \to SiO_2 + 4HCl $: Silicon tetrachloride undergoes hydrolysis with water; Si-Cl bonds are replaced by Si-O bonds from water. This is hydrolysis.
Step 5: Analyze option (4).
$ 2F_2 + 2H_2O \to 4HF + O_2 $: Here fluorine oxidizes the oxygen in water from $ -2 $ to $ 0 $ (in $ O_2 $), while F is reduced from $ 0 $ to $ -1 $. This is an oxidation-reduction (redox) reaction, not hydrolysis. Fluorine is not breaking water apart to incorporate OH or H into an F compound with the same structure - it is oxidizing water.
Step 6: Final answer.
\[ \boxed{2F_2 + 2H_2O \to 4HF + O_2\ \text{is NOT hydrolysis}} \]