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* Carbon = 79.9g, hydrogen = 20.1g (work out the mass of each element) * 79.9/12 = 6.66, 20.1/1 = 20.1 (divide mass by Atomic Mass number) * Ratio = 6.66 : 20.1 = 1:3 (simplify to find lowest ratio) * Therefore the simplest ratio and the empirical formula is CH3.

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15y ago
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11y ago

The gram atomic mass for carbon is 12.001 and the gram atomic mass for hydrogen is 1.008. Since a compound has constant composition, the percentages given show that a sample of 100 grams would contain 81.70 grams of carbon and 18.29 g of hydrogen. 81.70 grams of carbon contains 81.70/12.001 or 6.808 gram atomic masses of carbon, while 18.29 grams of hydrogen contains 18.14 gram atomic masses of hydrogen, for a ratio between hydrogen and carbon of about 2.66. The small integers that most closely approximate this ratio are 8 and 3. Therefore, the empirical formula is C3H8.

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12.000*n + 1.008*(2n+2) = 85.7 (CnH(2n+2) ) gives n = 6. So this hydrocarbon is C6H14, hexane

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Q: What is the empirical formula of a hydrocarbon with 85.7 mass carbon?
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How does one determine a molecule formula from the empirical formula?

The density or some other information must be given that allow you to find the molar mass. Calculate the empirical formula mass. Divide molar mass by empirical formula mass. This answer is multiplied by all subscripts of the empirical formula to get the molecular formula.


To determine the subscript of an element in a molecular formula the empirical mass must be multiplied by the actual mass?

The actual mass must be divided by the empirical mass. This was derived from the following equation: (subscript)(empirical formula) = (molecular formula) subscript = (molecular formula)/(empirical formula)


How does one determine a molecular formula from empirical formula?

molar mass over grams of elementThe above answer is somewhat correct. In order to find the molecular formula when given the empirical formula, you must first find the molar mass of the empirical formula.MOLAR MASS# atoms element A x Atomic Mass element A (Periodic Table) = mass A# atoms element B x atomic mass element B (periodic table) = mass B... etc.Add up all of the mass values found above and you have the molar mass.Then, after you have found the empirical formula's molar mass, you divide the molar mass of the molecular formula by the empirical formula's molar mass (solving for n).MOLECULAR FORMULA EQUATION: N (Empirical formula) (read as N times empirical formula) where:N = Molar mass substance---- Molar Mass emp. form.


How do you calculate Molecular formula from empirical formulaWhat could you do with that information to determine that the empirical and molecular formulas are related to one another by a factor of 6?

In order to find molecular formula from empirical formula, one needs to know the molar mass of the molecular formula. Then you simply divide the molar mass of the molecular formula by the molar mass of the empirical formula to find out how many empirical formulae are in the molecular formula. Then you multiply the subscripts in the empirical formula by that number.


How does one determine a molecular formula from the empirical form?

molar mass of unknown/molar mass of empirial = # of empirical units in the molecular formula. Example: empirical formula is CH2O with a molar mass of 30. If the molar mass of the unknown is 180, then 180/30 = 6 and molecular formula will be C6H12O6

Related questions

How does one determine a molecule formula from the empirical formula?

The density or some other information must be given that allow you to find the molar mass. Calculate the empirical formula mass. Divide molar mass by empirical formula mass. This answer is multiplied by all subscripts of the empirical formula to get the molecular formula.


To determine the subscript of an element in a molecular formula the empirical mass must be multiplied by the actual mass?

The actual mass must be divided by the empirical mass. This was derived from the following equation: (subscript)(empirical formula) = (molecular formula) subscript = (molecular formula)/(empirical formula)


What is the molecular formula of a compound that has a mass of 54 and an empirical formula of c2h2?

This is a hydrocarbon called Acetylene (IUPAC name : Ethyne). It contains two carbon atoms joined with a triple bond, and 2 hydrogen atoms connected to the two carbon atoms with a single bond. Its structure : H-C≡C-H


How does on determine a molecular formula from the empirical formula?

molar mass over grams of elementThe above answer is somewhat correct. In order to find the molecular formula when given the empirical formula, you must first find the molar mass of the empirical formula.MOLAR MASS# atoms element A x Atomic Mass element A (Periodic Table) = mass A# atoms element B x atomic mass element B (periodic table) = mass B... etc.Add up all of the mass values found above and you have the molar mass.Then, after you have found the empirical formula's molar mass, you divide the molar mass of the molecular formula by the empirical formula's molar mass (solving for n).MOLECULAR FORMULA EQUATION: N (Empirical formula) (read as N times empirical formula) where:N = Molar mass substance---- Molar Mass emp. form.


How does one determine a molecular formula from empirical formula?

molar mass over grams of elementThe above answer is somewhat correct. In order to find the molecular formula when given the empirical formula, you must first find the molar mass of the empirical formula.MOLAR MASS# atoms element A x Atomic Mass element A (Periodic Table) = mass A# atoms element B x atomic mass element B (periodic table) = mass B... etc.Add up all of the mass values found above and you have the molar mass.Then, after you have found the empirical formula's molar mass, you divide the molar mass of the molecular formula by the empirical formula's molar mass (solving for n).MOLECULAR FORMULA EQUATION: N (Empirical formula) (read as N times empirical formula) where:N = Molar mass substance---- Molar Mass emp. form.


How do you calculate Molecular formula from empirical formulaWhat could you do with that information to determine that the empirical and molecular formulas are related to one another by a factor of 6?

In order to find molecular formula from empirical formula, one needs to know the molar mass of the molecular formula. Then you simply divide the molar mass of the molecular formula by the molar mass of the empirical formula to find out how many empirical formulae are in the molecular formula. Then you multiply the subscripts in the empirical formula by that number.


The empirical formula for cumene a compound containing only carbon and hydrogen is C3H4. Its Molecular mass is 120 g. What is the molecular formula for cumene?

This molecular formula is C9H12.


What does an empirical formula show?

the empirical formula of a compound tells you the proportions of the elements in the compound. with that information you can make some inferences about the identity of the compound. for example a compound with an empirical formula CH4 tells us that for every carbon atom there are four hydrogen atoms. this means that the compound is methane because no other hydrocarbon can have these roportions (try drawing the lewis structure for C2H8, which doesnt exist. you cant!)


Explain why the percent composition of certain compounds are not sufficient to determine the compounds molecular formulas?

Because unlike the empirical formula, the molecular formula does not have to be the simplest ratio.If by chance you are given the percent composition of the elements in a substance, you could calculate the empirical formula and then the empirical formula's mass. However, the molecular formula equation is molecular formula= (empirical formula)n, where n is the mass of the molecular formula divided by the mass of the empirical formula. You would, therefore, need to know the mass belonging to the molecular formula, which you are not given.


How does one determine a molecular formula from the empirical form?

molar mass of unknown/molar mass of empirial = # of empirical units in the molecular formula. Example: empirical formula is CH2O with a molar mass of 30. If the molar mass of the unknown is 180, then 180/30 = 6 and molecular formula will be C6H12O6


What steps are used to convert an empirical formula into a molecular formula?

By determining the molecular mass, then dividing the molecular mass by the formula mass of the empirical formula to determine by what integer the subscripts in the empirical formula must be multiplied to produce the molecular formula with the experimentally determined molecular mass.


What is the carbon formula?

Carbon is a chemical element, and it has C as its chemical symbol. It does not have a chemical formula because it is (as stated) a chemical element, and not a chemical compound.