Examples of Emperical Formula
Example 1: The Empirical formula of Butane is C2H5. Calculate the Molecular formula when the measured mass of the compound is 58.1224
Solution:
Atomic mass of given empirical formula = 2(C) + 5(H) = 2(12.011) + 5(1.00784) = 29.0612u
But, the measured molecular mass for Butane is given as 58.1224u
By using the expression, Molecular formula = n × empirical formula
n = weight of molecular formula/weight of empirical formula
= 58.1224/29.0612
= 2
Molecular formula = 2 × C2H5
= C4H10
Example 2: Find a molecular formula for the compound having the empirical formula CH2 with a molecular weight of 42.08.
Solution:
Atomic mass of given empirical formula = C + 2(H) = 12.011 + 2(1.00784) = 14.02u
But, the measured molecular mass for given compound is 42.08u
By using the expression, Molecular formula = n × empirical formula
n = weight of molecular formula/weight of empirical formula
= 42.08/14.02
= 3
Molecular formula = 3 × CH2
= C3H6
Example 3: Find the empirical for the compound with molecular formula C6H12O6.
Solution:
C6H12O6 = 6 × CH2O
We know that Molecular Formula = n × Empirical Formula
Here, n = 6
So empirical formula for the given compound is CH2O.
Empirical Formula
Empirical Formula in chemistry is defined as the simplest ratio of the elements present in the compound. It does not take into account that these elements are connected with each other in any manner. This is explained in the formula of Glucose as we know that the formula for Glucose is C6H12O6 here we see that there are 3 atoms in the glucose molecule, they are carbon, hydrogen, and oxygen, Now the ratio of these elements is 1: 2: 1 i.e. for one molecule of hydrogen we have 2 molecules of hydrogen and one molecule of oxygen. So its empirical formula is CH2O. It doesn’t tell us how many elements of each element are there in the Glucose molecule.
In this article, we will learn about the Empirical Formula in Chemistry, Molecular Formula, the Difference between Molecular Formula and Empirical Formula, and others in detail.
Table of Content
- Empirical Formula
- Molecular Formula
- Molecular Formula Vs Empirical Formula
- Empirical Formula of Various Compounds
- How to Find Molecular Formula from Empirical Formula?