molar mass over grams of element
The 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.
molar mass over grams of element
The 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.
C2H4O2=molecular formula, basically you multiply the empirical formula by 2.
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)
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 and the molar mass
Not completely. The empirical formula of a substance can be determined from its percent composition, but a determination of molecular weight is needed to decide which multiple of the empirical formula represents the molecular formula.
The empirical formula is the formula in its most simplified terms. The molecular formula is how many moles there actually are (the empirical formulat multiplied by a factor).
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.
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
A molecular formula is identical to the empirical formula, and is based on quantity of atoms of each type in the compound.The relationship between empirical and molecular formula is that the empirical formula is the simplest formula, and the molecular can be the same as the empirical, or some multiple of it. An example might be an empirical formula of C3H8. Its molecular formula may be C3H8 , C6H16, C9H24, etc. Looking at it the other way, if the molecular formula is C6H12O6, the empirical formula would be CH2O.
A molecular formula is identical to the empirical formula, and is based on quantity of atoms of each type in the compound.The relationship between empirical and molecular formula is that the empirical formula is the simplest formula, and the molecular can be the same as the empirical, or some multiple of it. An example might be an empirical formula of C3H8. Its molecular formula may be C3H8 , C6H16, C9H24, etc. Looking at it the other way, if the molecular formula is C6H12O6, the empirical formula would be CH2O.
A molecular formula is identical to the empirical formula, and is based on quantity of atoms of each type in the compound.The relationship between empirical and molecular formula is that the empirical formula is the simplest formula, and the molecular can be the same as the empirical, or some multiple of it. An example might be an empirical formula of C3H8. Its molecular formula may be C3H8 , C6H16, C9H24, etc. Looking at it the other way, if the molecular formula is C6H12O6, the empirical formula would be CH2O.
A molecular formula is identical to the empirical formula, and is based on quantity of atoms of each type in the compound.The relationship between empirical and molecular formula is that the empirical formula is the simplest formula, and the molecular can be the same as the empirical, or some multiple of it. An example might be an empirical formula of C3H8. Its molecular formula may be C3H8 , C6H16, C9H24, etc. Looking at it the other way, if the molecular formula is C6H12O6, the empirical formula would be CH2O.