Which information must be known about a compound to find the molecular formula from the empirical formula? densityformula masspercent compositionmole ratio

To determine the molecular formula from the empirical formula, the mole ratio must be known. This is to know which is the least amount that can be divided to each number of moles. Density is irrelevant to this data. Mass percent is constant to both molecular formula and empirical formula so this is not needed.