How to find the empirical formula of an unknown reactant?

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In summary, the empirical formula of an unknown reactant is the simplest whole number ratio of atoms present in a compound, representing its fundamental composition. To determine the empirical formula, the mass of each element must be known and divided by its molar mass to get the moles of each element. The empirical formula can be different from the molecular formula, as the latter represents the actual number of atoms in a molecule. The empirical formula tells us the relative number of atoms in a compound and can be used to determine the molecular formula if the molecular mass is known.
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Homework Statement


The problem is attached in uploads

Homework Equations


The periodic table, all other relevant info given in question

The Attempt at a Solution


Well, first I would attempt to convert all the products into moles so I can compare the more rations of the products. Firstly, the CO2 become 0.950 moles and H2O becomes 0.19 moles. After that I am completely lost. Thanks

Never mind I got it. Thanks anyways
 

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Note: this kind of a problem is called "combustion analysis" and is quite common.
 

FAQ: How to find the empirical formula of an unknown reactant?

What is the empirical formula of an unknown reactant?

The empirical formula of an unknown reactant is the simplest whole number ratio of atoms present in a compound. It represents the fundamental composition of the compound.

How do I determine the empirical formula of an unknown reactant?

To determine the empirical formula, you will need to know the mass of each element present in the compound. Then, divide the mass of each element by its molar mass to get the moles of each element. Next, divide the moles of each element by the smallest number of moles to get the simplest whole number ratio. This will give you the empirical formula.

Can the empirical formula be different from the molecular formula?

Yes, the empirical formula can be different from the molecular formula. The molecular formula represents the actual number of atoms of each element in a molecule, while the empirical formula represents the simplest ratio. However, if the molecular formula is known, the empirical formula can be determined by dividing the molecular formula by the greatest common factor of the subscripts.

What does the empirical formula tell us about a compound?

The empirical formula tells us the relative number of atoms of each element in a compound. It gives us information about the fundamental composition of the compound, which can help in identifying and classifying it.

Can the empirical formula be used to determine the molecular formula?

Yes, the empirical formula can be used to determine the molecular formula if the molecular mass of the compound is known. By comparing the molar mass of the empirical formula to the molecular mass, the number of repeating units in the molecule can be determined, thus giving the molecular formula.

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