is the melting point determination of crude benzoic acid recyustalization is higher or lower?

Answer 1

Your question makes no sense grammatically. You can't use the word "is" twice.

Also, recyustalization is not a word.

Answer 2

What you may mean is to ask if crude benzoic acid has a higher or lower melting point than recrystallized benzoic acid. The purer benzoic acid has a higher melting point than impure benzoic acid.