Why is benzoic acid is extracted into ether then extracted into an alkali solution prior to being precipitated with strong acid in its preparation with grignard reagent?

When you're attempting to extract benzoic acid from other organic compounds, it is necessary to change its pH by adding a layer of an basic compound such as 1M NaOH so that the benzoic acid then can be separated from the organic layer within a separatory funnel. When in NaOH, the benzoic acid loses a proton and thus becomes its conjugate base (the benzoate ion). The benzoate ion is charged and thus become miscible in the aqueous layer. To extract benzoic acid (ie get it to precipitate out of solution), a strong acid such as HCl must be added to solution. After the extraction, lower the pH of the solution, and recrystalize (use ice after the recrystalization to get benzoic acid crystals to crash out).