Better method for preparation ofBeF2, among the following is

Strategy: Identify the best preparative method for$\ce{BeF2}$among the given options.

Step 1: Why Direct Route Fails -$\ce{Be + F2 ->[\ \Delta\ ] BeF2}$— technically feasible but not preferred commercially. -$\ce{BeO + C + F2}$— ClO₄ route, possible but not standard. -$\ce{BeH2 + F2}$— dangerous;$\ce{BeH2}$is itself difficult to handle.

Step 2: Preferred Industrial Method The better method involves thermal decomposition of ammonium tetrafluoroberyllate :$\ce{(NH4)2[BeF4] \xrightarrow{\Delta} BeF2 + 2NH4F}$This is a safe, controlled method yielding pure anhydrous$\ce{BeF2}$. ✅$\boxed{\text{Answer: (B) }\ce{(NH4)2BeF4 ->[\ \Delta\ ] BeF2}}$