# What is the chemical composition of the grignard reagent?

What is the actual chemical composition of the grignard reagent and what is the method of preparation? Can it be prepared in college laboratories?

A Grignard reagent is an organomagnesium halide of the generic form $\ce{RMgX}$, where $\ce{R}$ is a hydrocarbon group and $\ce{X}$ is a halide, usually $\ce{Cl}$, $\ce{Br}$, or $\ce{I}$.
$$\ce{PhBr(C6H5Br) + Mg ->[][\ce{Et2O}]PhMgBr}$$