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.
Empirical formula in Chemistry is the simplest formula for a compound. It is defined as the ratio of subscripts of the smallest possible whole number of the elements present in the formula. This formula gives information about the ratio of the number of atoms in the compound.
There is a relationship between molecular formula and empirical formula, which is given by,
Molecular Formula = n × Empirical Formula
where,
To get a better understanding of the empirical formula, let's look into an example,
Molecular formula of acetylene is C2H2
Emeperical Formula Definition
Empirical formula is the simplest ratio of number of each different atom present in the compound
Empirical Formula = Molecular Formula/n
For Example, C2H2 can be represented as 2(CH)
So, Empirical formula of Acetylene is CH
Molecular Formula of a compound is defined as the formula that tells us how may atoms are there in a molecule of the compound. It tells us exactly how many atoms are required to form a molecule. We know that molecular formula of water is H2O. This signifies that in a water molecule we have two atoms of Hydrogen and an Oxygen atoms linked together to form a water molecule.
Molecular Formula Examples
Molecular Formula for various compounds are,
- Molecular Formula of Benzene: C6H6
- Molecular Formula of Ethyl Alcohol: C2H5OH
- Molecular Formula of Ethane: C2H6
The molecular formula and empirical formula of various compounds are different (in some special cases they can be same). They represent different properties of the compound. The differences between Empirical Formula and the Molecular Formula of the compound are given below in the table.
|
Empirical Formula represent the simplest ratio in which the atoms combined to form a molecule. | Molecular formula tells us that exactly how many atoms combined to form molecule. |
Example: Empirical Formula for Butane is C2H5 | Example: Molecular Formula for Butane is C4H10 |
Emperical formula of any compound only tells us that how many atoms are in any compound and they are in which ratio. Empirical formula for some important compounds are discussed below.
Empirical Formula of C6H12O6(Glucose)
- Empirical Formula of Glucose is CH2O
Empirical Formula of Rust
- Empirical Formula of Rust i.e. Iron Oxide is Fe2O3
Empirical Formula of Benzene
- Empirical Formula of Benzene is CH
Empirical Formula of Urea
- Empirical Formula of Urea is CH4N2O
Empirical Formula of Acetic Acid
- Empirical Formula of Urea is CH2O
Empirical formula for Magnesium Oxide
- Empirical Formula of Magnesium Oxide is MgO
We can easily calculate the molecular formula from empirical formula by following the steps added below,
Step 1: Find molar mass of the Empirical Formula.
Step 2: Find the molecular mass of the given compound and divide the following molecular formula by the empirical formula from step 1.
Step 3: The whole number is obtained as a result of division. Multiply each atom of the empirical formula in subcript by this whole number.
This is the required molecular formula.
Read More,
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.
Similar Reads
Statistics in Maths Statistics is the science of collecting, organizing, analyzing, and interpreting information to uncover patterns, trends, and insights. Statistics allows us to see the bigger picture and tackle real-world problems like measuring the popularity of a new product, predicting the weather, or tracking he
3 min read
Introduction to Statistics
Mean
Mean in StatisticsIn statistics, three measures are defined as central tendencies that are: Mean, Median, and Mode, where the mean provides the average value of the dataset, the median provides the central value of the dataset, and the most frequent value in the dataset is the mode.Calculation of central tendency, su
15+ min read
How to find Mean of grouped data by direct method?Statistics involves gathering, organizing, analyzing, interpreting, and presenting data to form opinions and make decisions. Applications range from educators computing average student scores and government officials conducting censuses to demographic analysis. Understanding and utilizing statistica
8 min read
How to Calculate Mean using Step Deviation Method?Step Deviation Method is a simplified way to calculate the mean of a grouped frequency distribution, especially when the class intervals are uniform. In simple words, statistics implies the process of gathering, sorting, examining, interpreting and then understandably presenting the data to enable o
6 min read
Median
Mode
Frequency Distribution - Table, Graphs, Formula A frequency distribution is a way to organize data and see how often each value appears. It shows how many times each value or range of values occurs in a dataset. This helps us understand patterns, like which values are common and which are rare. Frequency distributions are often shown in tables or
11 min read
Cumulative frequency Curve In statistics, graph plays an important role. With the help of these graphs, we can easily understand the data. So in this article, we will learn how to represent the cumulative frequency distribution graphically.Cumulative FrequencyThe frequency is the number of times the event occurs in the given
9 min read
Mean Deviation The mean deviation (also known as Mean Absolute Deviation, or MAD) of the data set is the value that tells us how far each data is from the center point of the data set. The center point of the data set can be the Mean, Median, or Mode. Thus, the mean of the deviation is the average of the absolute
12 min read
Standard Deviation - Formula, Examples & How to Calculate Standard deviation is a statistical measure that describes how much variation or dispersion there is in a set of data points. It helps us understand how spread out the values in a dataset are compared to the mean (average). A higher standard deviation means the data points are more spread out, while
15+ min read
Variance Variance is a number that tells us how spread out the values in a data set are from the mean (average). It shows whether the numbers are close to the average or far away from it.If the variance is small, it means most numbers are close to the mean. If the variance is large, it means the numbers are
12 min read