Empirical to Molecular Formulas [ENDORSED]
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Empirical to Molecular Formulas
I understand how to find empirical formulas, but am unclear on how you would transfer that into a molecular formula. What kind of further information do you need to find the true molecular formula?
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Re: Empirical to Molecular Formulas
You would need the molar mass of the molecule you are trying to find. Then you would divide that molar mass by the molar mass of the empirical formula and get a number. If the number is like 2.9 or 5.1, you can round it to a whole number. If it is not a whole number, I suggest checking your work because something might be wrong in your calculations. Then multiply that whole number with each of the atoms in the empirical formula, and then you get the molecular formula.
I hope this helps.
I hope this helps.
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Re: Empirical to Molecular Formulas
To find the molecular formula, you divide the molar mass of the compound by the molar mass of the empirical formula. This will give you a whole number or a number very close to a whole number. You then multiply all the subscripts in the empirical formula by the whole number you just found. Therefore, the further information you need to find the true molecular formula is the molar mass of the compound and the molar mass of the empirical formula.
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Re: Empirical to Molecular Formulas
Once you’ve found the empirical formula, you need to calculate its molar mass. The molar mass of the molecular formula will be given. You divide the molecular molar mass by the empirical molar mass and this will result in a whole number, approximately. To find the molecular formula, you multiply each of the subscripts in the empirical formula by that whole number.
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Re: Empirical to Molecular Formulas [ENDORSED]
You would need to find the factor by which you multiply the subscripts of the empirical formula with. This can be found by dividing the molar mass of the molecular formula (usually given in the problem) by the molar mass of the empirical formula! Hope that helps.
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Re: Empirical to Molecular Formulas
I think everyone has already answered your question. But to put it simply, use the molar mass and compare the empirical molar mass. If they match, molecular formula and empirical formula are the same. Otherwise, you'll have to divide the empirical mass by the given overall molar mass. Whatever closest whole number you get, you will multiply that to your current empirical subscripts. :D Hope this helps
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Re: Empirical to Molecular Formulas
LuveiaPangilinan 2C wrote:I think everyone has already answered your question. But to put it simply, use the molar mass and compare the empirical molar mass. If they match, molecular formula and empirical formula are the same. Otherwise, you'll have to divide the empirical mass by the given overall molar mass. Whatever closest whole number you get, you will multiply that to your current empirical subscripts. :D Hope this helps
To clarify one must divide the molar mass of the molecule by the molar mass of the empirical formula.
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