In lab an experiment was performed to determine the empirical formula of magnesium

oxide. Two trials were performed. Trial 1 had an initial mass of magnesium metal of

355 g. Trial 2 had an initial mass of magnesium metal of 0.299 g. Assuming that both

trials were performed in the same manner, which of the following statements is correct?

A) Trial 1 will have a larger ratio of Mg in the empirical formula than trial 2.

B) Trial 2 will have a smaller ratio of Mg in the empirical formula than trial 2.

C) Trial 1 will have the same calculated empirical formula as trial 2.

D) Trial 1 will have a different calculated empirical formula than trial 2.

The correct option is

C) Trial 1 will have the same calculated empirical formula as trial 2.

Explanation:

The empirical formula is the formula of a chemical compound that states the simplest whole number ratio of each of the atoms included in the compound. It is obtained by dividing the mass of an element present in the compound by the element's molar mass to find the mole ratio of the elements. The obtained mole value for each element is then divided by the smallest number of moles obtained in the division.

By definition the composition and ratio of elements combined in a chemical compound is fixed, therefore trial 1 will have the same calculated empirical formula as trial 2.