SUMMARY OF CHEMICAL REACTION AND EQUATION
Class 10 Chemistry — Chapter 1 Complete Notes
1. Chemical Reaction, Reactants & Products
Chemical Reaction: When a substance reacts with itself or any other substance to form a substance
with one or more new chemical properties, this is called a Chemical Reaction.
Reactants: The substances which participate in a chemical reaction are called Reactants.
Products: The new substances obtained after a chemical reaction are called Products.
2. Equations
(A) Word-Equations
Writing a description of a chemical reaction in words is called a Word-equation. It is the simplest
way to write a chemical reaction.
Example: When a Magnesium ribbon is burnt in Oxygen, it gets converted to Magnesium Oxide.
Magnesium + Oxygen Magnesium Oxide
[ Reactants ] [ Product ]
A word equation shows change of reactants to products through an arrow placed between them.
The reactants are written on the left-hand side (LHS) with a plus sign (+) between them. Products
are written on the Right Hand Side (RHS) with a plus sign (+). The arrowhead points towards the
products, and shows the direction of the reaction.
REACTANTS (LHS) PRODUCTS (RHS)
(B) Chemical Equations
Representation of a chemical reaction by the use of symbols and chemical formulae of reactants
and products is called a Chemical Equation.
Example:
2Mg + O2 2MgO
3. Balanced Chemical Equation
The number of all the atoms remains equal in the reactants and products of a balanced chemical
equation. The chemical reaction must always be balanced, which is done by the hit or trial
method.
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Class 10 Chemistry — Chapter 1 Complete Notes
1. Chemical Reaction, Reactants & Products
Chemical Reaction: When a substance reacts with itself or any other substance to form a substance
with one or more new chemical properties, this is called a Chemical Reaction.
Reactants: The substances which participate in a chemical reaction are called Reactants.
Products: The new substances obtained after a chemical reaction are called Products.
2. Equations
(A) Word-Equations
Writing a description of a chemical reaction in words is called a Word-equation. It is the simplest
way to write a chemical reaction.
Example: When a Magnesium ribbon is burnt in Oxygen, it gets converted to Magnesium Oxide.
Magnesium + Oxygen Magnesium Oxide
[ Reactants ] [ Product ]
A word equation shows change of reactants to products through an arrow placed between them.
The reactants are written on the left-hand side (LHS) with a plus sign (+) between them. Products
are written on the Right Hand Side (RHS) with a plus sign (+). The arrowhead points towards the
products, and shows the direction of the reaction.
REACTANTS (LHS) PRODUCTS (RHS)
(B) Chemical Equations
Representation of a chemical reaction by the use of symbols and chemical formulae of reactants
and products is called a Chemical Equation.
Example:
2Mg + O2 2MgO
3. Balanced Chemical Equation
The number of all the atoms remains equal in the reactants and products of a balanced chemical
equation. The chemical reaction must always be balanced, which is done by the hit or trial
method.
Page 1 of 4
