Answer:
1,45 mL
Explanation:
The Grignard reaction is a very important organometallic chemical reaction where the Grignard reagent ( alkyl, vinyl, or aryl-magnesium halides) acts as nucleophile in order to the formation of Carbon-Carbon bonds.
In the problem, the phenylmagnesium chloride is the grignard reagent. The volume of 2.0 M phenylmagnesium chloride solution you need to add 2.9 mmol is:
2,9 mmol × [tex]\frac{1mL}{2,0mM}[/tex] = 1,45 mL
I hope it helps!