5 Important Chemical Reactions for CBSE Class 10 Science Board Exam

The chapter Chemical Reactions and Equations is an important part of CBSE Class 10 Science. Questions from this chapter are frequently asked in board exams based on chemical equations, reaction types, observations, and practical applications.

Students often find it difficult to remember different reactions and their products. A better approach is to understand the concept behind each reaction along with important observations and balanced chemical equations.

The following chemical reactions are important for quick revision and board exam preparation.

Important Chemical Reactions You Must Know for Class 10 Science

Chemical reactions provide us with an insight into the transformation of substances into different products. In the subject of science for Class 10, emphasis should be put on reactions that help to explain laboratory processes, practical uses in everyday life, and key chemical concepts.

Certain reactions keep recurring in the exams as they test students' knowledge about the reactants, products, reaction conditions, and observations.

Hydrogen Gas Formation Reaction

Another important reaction that takes place in this chapter is the reaction between zinc metal and dilute sulphuric acid. In this reaction, hydrogen gas is evolved from the reaction between zinc and dilute sulphuric acid.

Hydrogen gas can be detected through the use of a burning matchstick which produces a pop sound when placed near it.

Zn + H₂SO₄ → ZnSO₄ + H₂↑

This reaction is an example of a displacement reaction and is commonly asked in board exams.

Reactions Related to Metals and Their Purification

The reaction of steam with iron and the process of electrolytic refining are important concepts from the Metals and Non-Metals chapter.

When steam reacts with hot iron, hydrogen gas is released along with the formation of iron oxide. Similarly, electrolytic refining is used to obtain pure metals from impure metals.

Students should remember:

• The role of anode and cathode in electrolytic refining.

• Formation of anode mud due to impurities.

• Conditions required for metal reactions.

Carbon Dioxide Test and Lime Water Reaction

The reaction of carbon dioxide with calcium hydroxide solution is an important laboratory-based reaction.

When carbon dioxide is passed through lime water, it turns milky due to the formation of calcium carbonate.

CO₂ + Ca(OH)₂ → CaCO₃↓ + H₂O

This reaction is often asked in questions related to identifying carbon dioxide gas and chemical observations.

Micelle Formation in Soaps and Detergents

The process through which soaps and detergents clean is an equally important topic that Class 10 students need to understand.

The soap molecules create structures known as micelles when mixed with water. The hydrophobic end draws oil and grease, while the hydrophilic end sticks to the water molecules.

How to Prepare These Reactions for Board Exams?

In CBSE Class 10 Science exams, the student must study:

• Balanced chemical equation
• Reaction conditions
• Reaction type
• Important observations
• Daily life applications

Solving Sample Paper Class 10 CBSE assists the students in getting an idea about the new pattern of the exam.

The students can also refer to CBSE Previous Year Question Papers Class 10 to find out which reactions have been asked more number of times in the past years.

Chapter Chemical Reactions and Equations is a high-scoring chapter in CBSE Class 10 Science. By understanding important reactions along with their equations and observations, the students will be able to answer the questions asked in the board exams.