Question

hello, can someone give me the percent yield of this.This is a grignard synthesis, I used Acetophenone (1.215g) dissolved in diethyl ether and phenylmagnesium bromide was added (3.7 ml).

Answer 1

You need to first write the balanced chemical equation for t he reaction. You are probably talking of the following reaction.

From balanced equation , we have.,

= 120 g acetophenone react with = 181 g phenyl magnesium bromide.

= 1.215 g  acetophenone react with = 181 x 1.215 / 120 g

= 1.833 g PhMg Br.

But phenyl magnesium bromide is liquid, so we have to check whether we have taken required amount of PhMgBr or not

Density of PhMgBr = 1.14 g / mL

= mass percentage of solute = 2.61 / 262.5 x 100

= 0.99 %

= 1.14 g = 1 mL

therefore 1.833 g = 1.833 x 1 / 1.14 mL

= 1.61 mL

So, we had to take 1.61 mL of PhMgBr.