# Percent Composition Calculator

Percent Composition Calculator is a free online tool that finds the percentage of every element by weight in a chemical compound from its chemical formula. This tool takes the chemical compound formula as input and gives every chemical element mass percent and atom percent as output in a short span of time.

### What is Percent Composition?

The percentage composition of a chemical compound is defined as the ratio of the amount of every element to the amount of total elements presenr in the compound multiplied by per cent. Thus, the percent composition of a compound expresses its composition in terms of all the elements present.

### Percent Composition Formula

The percent composition of an element formula is given here:

Percent composition formula is **%C _{E} = (g^{E}/g^{T}) x 100**

Here,

- %C
_{E}is the percent composition of an element E - g
^{E}is the total amount of element E present in the compound - g
^{T}is the total amount of all elements present in the compound

### How to Compute Percentage Composition?

- Take any chemical formula to find percent composition.
- Find the molecular weight of the compound by multiplying its atomic mass by the no of atoms of each element in the molecule.
- Also, find the molar mass of each element in the compound.
- Using the percentage composition formula, get the answer.

**Example:**

Find the percent composition of every element in H_{2}SO_{4}.

**Solution:**

Given chemical compound is H_{2}SO_{4}

Calculate the molar mass of H_{2}SO_{4}

The molar mass of Hydrogen = 2 x 2.008 = 2.016 g/mol

The molar mass of Sulfur = 1 x 32.06 = 32.06 g/mol

The molar mass of Oxygen = 4 x 15.99 = 63.996 g/mol

Molecular weight of H_{2}SO_{4} = 2 x 1.008 + 32.06 + 4 x 15.999

= 98.07 amu = 98.07 g/mol

Percentage composition of each element in sulfuric acid is:

Hydrogen% = (2.016/98.07) x 100 = 2.0556%

Sulfur% = (32.06/98.07) x 100 = 32.69%

Oxygen% = (63.996/98.07) x 100 = 65.25%

### FAQ's on Percent Composition Calculator

**1. What is percentage composition?**

The percentage composition of a chemical compound is defined as the ratio of the amount of every element to the total amounts in the compound which is multiplied by 100.

**2. How to find percent composition?**

To calculate the percent composition of a compound, get the molar mass of every individual element along with the molar mass of the whole compound. Later, divide the element's molar mass by the whole molar mass and multiply it by 100 to obtain the percent composition.

**3. Is percent by mass the same as percentage composition?**

No, they are different. The mass percent is the percentage of a component in the compound while the percent composition is the percentage of a particular element in the compound.

**4. Calculate the percent composition of every element in water?**

The chemical formula of water is H₂O.

The molar mass of O = 16 x 1 = 16 g/mole

Molar mass of H = 1.01 x 2 = 2.02 g/mole

Percent composition of H = 2.02/(16 + 2.02) x 100 = 11.21%

Percent composition of O = 16/18.02 x 100 = 88.79%