Table of Contents
This set of MCQs is designed to help you understand the key concepts of combustion and flame, which are important topics in the Class 8 science curriculum. The “Combustion and Flame Class 8 MCQ” covers a wide range of topics, including the definition of combustion, the role of oxygen in the combustion process, the characteristics of different types of flames, and the practical applications of combustion and flame in everyday life.
These MCQs are a valuable resource for students preparing for their CBSE Class 8 exams, as they provide an opportunity to assess your knowledge and identify areas that require further study. The MCQs cover a variety of difficulty levels, from basic to more challenging questions, to help you strengthen your understanding of the subject.
In addition to the MCQs, you can also refer to the NCERT Solutions for Class 8 Science Chapter 6 Combustion and Flame, which provide detailed explanations and step-by-step solutions to help you better understand the concepts.
Whether you’re a student looking to reinforce your understanding of combustion and flame class 8 MCQs or an educator seeking to create engaging and challenging assessments, this set of MCQs is a must-have resource.
Combustion and Flame Class 8 MCQs PDF
Master the fundamentals of combustion and flame with our comprehensive MCQs PDF for Class 8. This valuable resource features 20 MCQs with answers and explanations, covering key topics like combustion, complete and incomplete combustion, catalysts, ignition, and more. Perfect for revision and assessment, this PDF is a must-have for students seeking to excel in the subject.
Combustion and Flame Class 8 MCQs
Combustion is a fundamental chemical process that powers our world, from the flames that cook our food to the engines that drive our vehicles. This set of MCQs for Class 8 students explores the science behind combustion, the nature of flames, and the factors that influence these essential phenomena.
Ques: What is combustion?
a) Burning of fuel
b) Melting of ice
c) Boiling of water
d) Freezing of water
Ans: a) Burning of fuel
Explanation: Combustion is the process of burning of fuel in the presence of oxygen, resulting in the release of heat and light.
Ques: What is the process of combustion?
a) Oxidation
b) Reduction
c) Decomposition
d) None of the above
Ans: a) Oxidation
Explanation: Combustion is an oxidation reaction, where a fuel reacts with oxygen to release heat and light.
Ques: What is the role of oxygen in combustion?
a) It helps in burning
b) It prevents burning
c) It has no effect on burning
d) It is not necessary for burning
Ans: a) It helps in burning
Explanation: Oxygen is essential for combustion to occur, as it reacts with the fuel to release heat and light.
Ques: What is the role of heat in combustion?
a) It helps in burning
b) It prevents burning
c) It has no effect on burning
d) It is not necessary for burning
Ans: a) It helps in burning
Explanation: Heat is necessary for combustion to occur, as it provides the energy required for the reaction to take place.
Ques: What is the role of fuel in combustion?
a) It helps in burning
b) It prevents burning
c) It has no effect on burning
d) It is not necessary for burning
Ans: a) It helps in burning
Ques: Explanation: Fuel is the substance that is burned in the presence of oxygen to release heat and light.
Ques: What is complete combustion?
a) Burning of fuel in the presence of air
b) Burning of fuel in the absence of air
c) Burning of fuel in the presence of oxygen
d) Burning of fuel in the absence of oxygen
Ans: a) Burning of fuel in the presence of air
Explanation: Complete combustion occurs when a fuel is burned in the presence of air, resulting in the release of heat and light.
Ques: What is incomplete combustion?
a) Burning of fuel in the presence of air
b) Burning of fuel in the absence of air
c) Burning of fuel in the presence of oxygen
d) Burning of fuel in the absence of oxygen
Ans: b) Burning of fuel in the absence of air
Explanation: Incomplete combustion occurs when a fuel is burned in the absence of air, resulting in the release of less heat and light.
Ques: What is the difference between complete combustion and incomplete combustion?
a) Complete combustion produces more heat
b) Incomplete combustion produces more heat
c) Complete combustion produces less heat
d) Incomplete combustion produces less heat
Ans: a) Complete combustion produces more heat
Explanation: Complete combustion produces more heat and light than incomplete combustion, as it involves the complete reaction of the fuel with oxygen.
Ques: What is the role of catalysts in combustion?
a) They help in burning
b) They prevent burning
c) They have no effect on burning
d) They are not necessary for burning
Ans: a) They help in burning
Explanation: Catalysts can help in combustion by increasing the rate of the reaction, allowing it to occur more quickly and efficiently.
Ques: What is the role of ignition in combustion?
a) It helps in burning
b) It prevents burning
c) It has no effect on burning
d) It is not necessary for burning
Ans: a) It helps in burning
Explanation: Ignition is the process of starting the combustion reaction, and it is necessary for the reaction to occur.
Ques: What is the role of fuel in combustion?
a) It helps in burning
b) It prevents burning
c) It has no effect on burning
d) It is not necessary for burning
Ans: a) It helps in burning
Explanation: Fuel is the substance that is burned in the presence of oxygen to release heat and light.
Ques: What is the role of oxygen in combustion?
a) It helps in burning
b) It prevents burning
c) It has no effect on burning
d) It is not necessary for burning
Ans: a) It helps in burning
Explanation: Oxygen is essential for combustion to occur, as it reacts with the fuel to release heat and light.
Ques: What is the role of heat in combustion?
a) It helps in burning
b) It prevents burning
c) It has no effect on burning
d) It is not necessary for burning
Ans: a) It helps in burning
Explanation: Heat is necessary for combustion to occur, as it provides the energy required for the reaction to take place.
Ques: What is the difference between combustion and burning?
a) Combustion is the process of burning
b) Burning is the process of combustion
c) Combustion and burning are the same
d) Combustion and burning are different
Ans: d) Combustion and burning are different
Explanation: Combustion is the process of burning, but not all burning is combustion. Combustion involves the complete reaction of the fuel with oxygen, while burning can occur without the presence of oxygen.
Ques: What is the role of catalysts in combustion?
a) They help in burning
b) They prevent burning
c) They have no effect on burning
d) They are not necessary for burning
Ans: a) They help in burning
Explanation: Catalysts can help in combustion by increasing the rate of the reaction, allowing it to occur more quickly and efficiently.
Ques: What is the role of ignition in combustion?
a) It helps in burning
b) It prevents burning
c) It has no effect on burning
d) It is not necessary for burning
Ans: a) It helps in burning
Explanation: Ignition is the process of starting the combustion reaction, and it is necessary for the reaction to occur.
Ques: What is the role of fuel in combustion?
a) It helps in burning
b) It prevents burning
c) It has no effect on burning
d) It is not necessary for burning
Ans: a) It helps in burning
Explanation: Fuel is the substance that is burned in the presence of oxygen to release heat and light.
Ques: What is the role of oxygen in combustion?
a) It helps in burning
b) It prevents burning
c) It has no effect on burning
d) It is not necessary for burning
Ans: a) It helps in burning
Explanation: Oxygen is essential for combustion to occur, as it reacts with the fuel to release heat and light.
Ques: What is the role of heat in combustion?
a) It helps in burning
b) It prevents burning
c) It has no effect on burning
d) It is not necessary for burning
Ans: a) It helps in burning
Explanation: Heat is necessary for combustion to occur, as it provides the energy required for the reaction to take place.
Ques: What is the difference between combustion and burning?
a) Combustion is the process of burning
b) Burning is the process of combustion
c) Combustion and burning are the same
d) Combustion and burning are different
Ans: d) Combustion and burning are different
Explanation: Combustion is the process of burning, but not all burning is combustion. Combustion involves the complete reaction of the fuel with oxygen, while burning can occur without the presence of oxygen.
Combustion and Flame Class 8 FAQs
What is Combustion?
Combustion is a chemical reaction between a fuel and an oxidizer that results in the release of heat and light. It is a fundamental process that powers various natural and industrial phenomena, such as fire, explosions, and the operation of engines.
What are the Essential Components of Combustion?
The essential components of combustion are a fuel, an oxidizer, and a source of ignition. The fuel can be a solid, liquid, or gas, while the oxidizer is typically oxygen. The source of ignition can be a spark, flame, or heat.
What are the Factors that Influence Combustion?
Several factors influence combustion, including the type and amount of fuel, the presence and concentration of oxygen, the temperature and pressure of the environment, and the presence of inhibitors or catalysts. These factors can affect the rate, efficiency, and safety of combustion.
What are the Types of Combustion?
There are several types of combustion, including complete combustion, incomplete combustion, and smoldering combustion. Complete combustion produces carbon dioxide and water vapor, while incomplete combustion produces carbon monoxide and other pollutants. Smoldering combustion involves a slow, low-temperature reaction.
