How do you find the empirical formula of magnesium oxide, when magnesium ribbon is burned in a crucible...and a #0.91*g# of material is present?

Question

Owen Ambrose · Accepted Answer

There are insufficient data here...........

We need (i) the tare mass of the crucible; (ii) the mass of the crucible and the magnesium metal BEFORE the reaction; (iii) the mass of the crucible and the resultant magnesium oxide AFTER the rxn. We interrogate the reaction: #Mg(s) + 1/2O_2(g) rarr MgO# And thus we need the mass of the metal, and the mass of the metal oxide. Do you have #0.91*g# of metal or #0.91*g# of metal oxide? We need BOTH masses to work out the stoichiometry.

Axel Alvarado · Answer

undefined To find the empirical formula of magnesium oxide, you need to determine the moles of magnesium and oxygen present in the compound. First, find the mass of oxygen by subtracting the mass of magnesium from the total mass. Then, calculate the moles of each element using their respective molar masses. Finally, divide the number of moles of each element by the smallest number of moles to obtain the simplest whole number ratio, which represents the empirical formula.