Let's assume that, as a preventative measure, you added 2 drops of the Vitride solution to your bromobenzene/Mg mixture when forming the Grignard reagent, but that your ethereal solution was completely dry (i.e. no water). That Vitride would reduce the 2-methylpropanal when it is added to the Grignard reagent.
What mass of reduced aldehyde would be formed after the workup of the reaction? HINT: Look carefully at the structure of Vitride.
2) Assuming Vitride reduced the aldehyde faster than the Grignard reagent, and also assuming the reduced aldehyde acted just like your desired product during the isolation of 2-methyl-3-heptanol, what is the mass percent of the reduced aldehyde in your product mixture?