Answer: 3.2*10²³ molecules BeF₂
Step-by-step explanation:
We will be converting from g to number of molecules by using our given g, molar mass of BeF₂(47.01g/mol), and Avogadro's number:
25g BeF₂(1 mol BeF₂/47.01g BeF₂)(6.022*10²³ molecules/1 mol) = 3.2*10²³ molecules BeF₂
I hope this helps! :)