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empirical formula of the compound

A compound of iron and oxygen is found to have a mass of 6.13 grams. If the mass of iron is determined to be 4.29 grams, what is the empirical formula of the compound?

Please give step by step answer in simplest way to do not making it complicated. Show all steps and solution please....

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1) A compound of iron and oxygen is found to have a mass of 6.13 grams. If the mass of iron is determined to be 4.29grams, what is the empirical formula of the compound?(6.13-4.29 = 1.84 g oxygen)
Right now you are comparing the masses of two different elements, which cannot be done properly (1 pound of gold is much less than 1 pound of feathers....)

We need to compare them on a mole by mole basis, so we figure out the molar masses for each.

MMFe = 56 g/mol
MMO = 16 g/mol
4.29 g /56 = 0.077 moles of iron
1.84 g/16 = 0.115 moles of oxygen

These need to be in whole number form, so we will divide by the smallest number...

0.077/0.077 = 1
0.115/0/077 = 1.5

Still not good enough, we need whole ...

Solution Summary

The solution shows how to find the empirical formula of the compound given its mass.

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