Chemical Reactions and Equations
Chemical Reaction: The transformation of chemical substance into another chemical substance is known as Chemical Reaction. For example: rusting of iron, setting of milk into curd, digestion of food, respiration, etc.
In chemical reaction new substance is formed which is completely different in properties from the original substance, so in a chemical reaction chemical change takes place.
Signs of Chemical Reaction
- Change of state of substance
- Change of colour of substance
- Evolution of heat
- Absorption of heat
- Evolution of gas
- Evolution of light
- Evolution of sound, etc.
Reactant and Product:
Reactant: Substances which take part in a chemical reaction are called reactants.
Product: New substance formed after a chemical reaction is called product.
Chemical Equation: Representation of chemical reaction using symbols of substances is called chemical equation.
Example: A + B ⇨ C + D
In this equation, A and B are called reactants and C and D are called the products. Arrow shows the direction of chemical reaction. Condition, if any, is written generally above the arrow.
No comments:
Post a Comment