posted by ANON .
If you had used a different mass of magneisium metal would you expect the empirical formula of the compiund to be the same? explain
If it is the same compound, the empirical formula is not dependent on the mass of the reactants.
You really should explain what you have done and what you are asking about. Actually, we don't know what you are asking.
I interpret the question differently than Bob Pursley. I ASSUME you are doing an experiment in which you weigh Mg metal, react it with oxygen and determine the empirical formula from the mass of the MgO that is formed. In that case the experimental empirical formula for the MgO may change if you weigh the amount of Mg incorrectly and weigh the MgO formed correctly. Thus you will have different moles of Mg versus the "proper" moles of oxygen and you may NOT end up with MgO but with Mg2O, MgO2, or some other weird formula. By the way, the statement made by Bob Pursley is correct but I think you have asked a slightly different question than his statement covers.