Main Types of Chemical Reactions with Equations and Examples
Types of Chemical Reactions is essential in chemistry and helps students understand various practical and theoretical applications related to this topic.
What is Types of Chemical Reactions in Chemistry?
A chemical reaction refers to a process where one or more substances (reactants) change into one or more different substances (products) by rearrangement of atoms.
This concept appears in chapters related to chemical equations, classification of reactions, and everyday chemical processes, making it a foundational part of your chemistry syllabus.
Types of Chemical Reactions
There are several types of chemical reactions in chemistry. The main types include:
- Combination Reaction: Two or more reactants combine to form a single product.
Equation: A + B → AB - Decomposition Reaction: A single compound breaks down into two or more simpler substances.
Equation: AB → A + B - Displacement Reaction: A more reactive element displaces a less reactive element from its compound.
Equation: A + BC → AC + B - Double Displacement Reaction: Two compounds exchange ions to produce two new compounds.
Equation: AB + CD → AD + CB - Redox Reaction: Oxidation and reduction occur together (electron transfer).
- Combustion Reaction: A substance reacts with oxygen, releasing energy as heat and light.
- Precipitation Reaction: An insoluble solid (precipitate) forms when two aqueous solutions are mixed.
- Neutralization Reaction: An acid reacts with a base to produce salt and water.
Examples of Each Reaction Type
| Type | General Equation | Example |
|---|---|---|
| Combination | A + B → AB | 2H2 + O2 → 2H2O |
| Decomposition | AB → A + B | 2H2O2 → 2H2O + O2 |
| Single Displacement | A + BC → AC + B | Zn + 2HCl → ZnCl2 + H2 |
| Double Displacement | AB + CD → AD + CB | AgNO3 + NaCl → AgCl + NaNO3 |
| Redox | Oxidation/Reduction | Fe + CuSO4 → FeSO4 + Cu |
| Combustion | Fuel + O2 → CO2 + H2O | CH4 + 2O2 → CO2 + 2H2O |
| Precipitation | Aqueous + Aqueous → Solid + Aqueous | BaCl2 + Na2SO4 → BaSO4↓ + 2NaCl |
| Neutralization | Acid + Base → Salt + Water | HCl + NaOH → NaCl + H2O |
Concept Table: Quick Reference
| Reaction Type | Pattern | Key Example |
|---|---|---|
| Combination | A + B → AB | 2Mg + O2 → 2MgO |
| Decomposition | AB → A + B | 2KClO3 → 2KCl + 3O2 |
| Single Displacement | A + BC → AC + B | Fe + CuSO4 → FeSO4 + Cu |
| Double Displacement | AB + CD → AD + CB | Na2SO4 + BaCl2 → BaSO4 + 2NaCl |
| Redox | Ox/Loss & Red/Gain (e–) | Zn + CuSO4 → ZnSO4 + Cu |
Types of Chemical Reactions in the Syllabus (Class 10)
- Combination Reaction
- Decomposition Reaction
- Displacement Reaction
- Double Displacement Reaction
- Redox Reaction
- Precipitation, Combustion, and Neutralization are common in lab practicals and objective questions.
Worksheet, PDF & Downloadable Resources
- Download topic notes and worksheets for types of chemical reactions from Vedantu’s resources section. Get instant practice on classifying, writing, and balancing reaction equations.
- Practice worksheet answer keys are included with every worksheet, making revision easier.
Practical Applications and Everyday Examples
- Rusting of iron (Redox Reaction)
- Cooking food (Decomposition)
- Respiration (Redox + Decomposition)
- Baking cake with baking soda (Decomposition and Displacement)
- Vinegar and baking soda (Double Displacement and Gas Evolution)
- Burning candle (Combustion)
Relation with Other Chemistry Concepts
Understanding types of chemical reactions is closely related to stoichiometry, balancing chemical equations, and the reactivity series. It also aids in topics like redox reactions and energy changes in reactions.
Step-by-Step Reaction Example
1. Identify the reaction type.You are given: Zn + 2HCl → ZnCl2 + H2
2. Zn (zinc) is more reactive than H (hydrogen) in HCl. It replaces H.
3. The reaction forms zinc chloride and releases hydrogen gas.
4. Final Answer: This is a single displacement reaction.
Lab or Experimental Tips
Remember combination reactions as “building up” and decomposition as “breaking down.” For quick identification, count the number of reactants and products. Vedantu educators often use colored test tubes, gas evolution, or precipitate formation in experiments to help students visualize these changes.
Try This Yourself
- Identify the type of reaction: CaCO3 → CaO + CO2
- Write a balanced equation of a neutralization reaction.
- Name a daily life example for each reaction type given above.
Final Wrap-Up
We explored types of chemical reactions—their definitions, patterns, and real-life uses. Mastering these helps you solve problems faster and relate chemistry to daily life. For deeper learning and exam tips, access live sessions and notes by Vedantu educators.
Balancing Chemical Equations
Combination Reaction
Displacement Reaction
Redox Reaction
FAQs on Types of Chemical Reactions: Definitions, Examples & Worksheet
1. What are the four main types of chemical reactions?
The four main types of chemical reactions are:
• Combination reaction (two or more substances combine)
• Decomposition reaction (a compound splits into simpler substances)
• Displacement reaction (an element replaces another in a compound)
• Double displacement reaction (two compounds exchange ions to form new compounds)
2. What is a redox reaction? Give one example.
A redox reaction involves simultaneous oxidation and reduction.
• Oxidation: Loss of electrons
• Reduction: Gain of electrons
Example: Zn + CuSO4 → ZnSO4 + Cu (Here, Zn is oxidized; Cu2+ is reduced.)
3. How can you identify the type of chemical reaction from an equation?
To identify the reaction type, examine the number and kind of reactants and products:
• Combination: Two or more reactants form one product
• Decomposition: One compound breaks apart
• Displacement: Single element exchanges place
• Double displacement: Exchange of ions between two compounds
Observe the equation pattern and substances involved.
4. What is the difference between displacement and double displacement reactions?
Displacement reaction: An element replaces another in a compound (A + BC → AC + B).
Double displacement reaction: Ions of two compounds exchange places to form new compounds (AB + CD → AD + CB).
Key difference: Displacement involves one exchange; double displacement involves two.
5. Give two examples of each main type of chemical reaction.
Examples:
Combination:
• H2 + Cl2 → 2HCl
• CaO + H2O → Ca(OH)2
Decomposition:
• 2H2O2 → 2H2O + O2
• CaCO3 → CaO + CO2
6. Where are chemical reactions used in daily life?
Chemical reactions occur everywhere in daily life:
• Digestion: Decomposition of food
• Rusting of iron: Redox reaction
• Baking soda and vinegar: Double displacement
• Respiration: Redox reaction
These examples connect chemistry with real-world processes.
7. What are the signs that a chemical reaction has taken place?
Signs of a chemical reaction include:
• Change in color
• Formation of gas (bubbles)
• Change in temperature (heat absorbed or evolved)
• Formation of a precipitate
• Change in odor
8. How do exothermic and endothermic reactions relate to types of chemical reactions?
Any chemical reaction can be exothermic or endothermic depending on energy flow:
• Exothermic: Releases heat energy (e.g., combustion, neutralization)
• Endothermic: Absorbs heat energy (e.g., thermal decomposition)
This property is independent of reaction classification.
9. Can a reaction belong to more than one category?
Yes, some reactions fit multiple categories.
• A reaction can be both a decomposition and a redox process.
• For example, decomposition of hydrogen peroxide is also a redox reaction.
10. Do all chemical reactions go to completion?
No, some chemical reactions are reversible and do not go to completion.
• Reversible reactions: Products can re-form reactants
• Example: Double displacement in equilibrium systems
Reversibility depends on reaction conditions.
11. What is the importance of balancing chemical equations when studying types of chemical reactions?
Balancing ensures the number of atoms is equal on both sides of the equation:
• Maintains the Law of Conservation of Mass
• Helps correctly identify and classify reaction types
• Avoids calculation errors in problems
12. What role do catalysts play in chemical reactions?
Catalysts speed up chemical reactions without being consumed:
• Affect the rate, not the classification
• Are important in processes like decomposition
• Do not change the reactants or products formed
