What is a Chemical Equation?

A chemical equation is a concise representation of a chemical reaction using symbols and formulas. It shows the reactants, the substances you start with and the products, the substances are produced at the end of the reaction.

1. Reactants: These are the substances present at the beginning of a chemical reaction. They are written on the left side of the arrow.
2. Products: These are the substances which are formed as a result of the chemical reaction. They are written on the right side of the arrow.
3. Arrow (→): The arrow indicates the direction of the reaction, showing the conversion of reactants into products.

Example: Let’s consider a simple reaction where hydrogen gas (H₂​) reacts with oxygen gas (O₂​) to form water (H₂​O).

2H₂​ + O_2​ → 2H₂​O

In this equation:

• 2H_2​ and O_2​ are the reactants.
• 2H₂​O is the product.
• The numbers in front of the formulas (coefficients) indicate the ratio in which the substances react or are produced. In this case, it means two molecules of hydrogen gas react with one molecule of oxygen gas to produce two molecules of water.

Skeletal Equation:

Let’s consider the following equation

Mg +O₂ → MgO

Number of atoms of all elements are not equal in reactants and products is called This typer of equations Unbalanced chemical equation.

Unbalanced chemical equation is also known as skeletal equation

Balancing Equations:

According to Law of Conservatation of mass , mass (matter) is neither created nor destroyed during any chemical reaction.

It’s important to note that the number of atoms of each element on the reactants side must be equal to the number of atoms of the same element on the products side. This is called balancing the chemical equation.

For example, the equation above is already balanced. If it were not, you might need to adjust the coefficients to ensure that the number of atoms on both sides of the arrow is the same.

Consider an Examples:

CaO + CO₂ → CaCO₃

the equation given above is already balanced.

Element	Number of atoms in Reactants	Number of atoms in products
Ca	1	1
C	1	1
O	3	3

All the elements of Calcium, Carbon and Oxygen are equal in reactants and products.

H₂ + Cl₂ → HCl

The above equation is not balanced. you might need to adjust the coefficients to ensure that the number of atoms On both sides of the arrow is the same as given below

H₂ + Cl₂ → 2HCl

Note: We should not adjest Subscript value of any reactant or product. We should change only coefficient values.

Conclusion: Understanding chemical equations is essential for comprehending chemical reactions. They provide a way to communicate the substances involved in a reaction and the ratios in which they combine. Balancing chemical equations ensures that the law of conservation of mass is obeyed, meaning no atoms are created or destroyed during a chemical reaction.

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