Science-Combustion and Flame-Sainik School Class 9 Coaching Center Study Material Notes Jalandhar-ANAND CLASSES

ANAND CLASSES study material notes on combustion and flame serve as a comprehensive and indispensable resource for students preparing for the Sainik School Entrance Exam.

With detailed explanations, practice questions, and expert guidance from experienced faculty members, students are well-equipped to tackle the exam with confidence and excel in their academic pursuits.

Access the study material today and embark on your journey towards success with ANAND CLASSES.

Explain Combustion Process

• A chemical process in which a substance reacts with oxygen to give off heat and light is called combustion.
• The burning of wood is an example of combustion.

Combustible and Non-Combustible Substances

• Substances which easily catch fire are combustible substances, such as paper, coal, and wood.
• Substances which do not catch fire readily are non-combustible substances, such as sand, water, and glass.

Wood and Candle Flame

Fuel

• Any substance, upon combustion, produces a usable amount of energy known as fuel. For example, fossil fuels, biogas, nuclear energy, etc.
• Fuels can be solid, liquid or gas, depending on their state.
• On the basis of their occurrence, it can be either natural or artificial.

Ignition Temp

The lowest temperature at which a combustible substance catches fire when heated in air is called its ignition temperature.

Inflammable Substances

The substances which have very low ignition temperatures and can easily catch fire with a flame are known as inflammable substances, for example, diesel, LPG, and acetone.

Fire

• Fire is the result of a chemical combustion reaction between oxygen and some sort of fuel.​​​​​​
• How long a fire lasts depends on how much fuel and oxygen are available.

Candle Flame

Fire Triangle

For the generation of fire, we need three things to be present simultaneously.

• Some sort of fuel or combustible material.
• A heat source to raise the temperature of the fuel to its ignition temperature.
• Enough oxygen to sustain combustion. So, if we remove any one of these resources, the fire can be controlled.

Flame

• Flame is the visible and gaseous part of the fire.
• What we see as the flame is the light energy released due to the combustion of fuel.

Zones of Candle Flame

Structure of Flame

• The outermost zone is the hottest among all zones and is blue in colour, and this is due to complete combustion. It is the non-luminous part of the flame.
• The middle zone of the candle flame is moderately hot and yellow in colour, and partial combustion of fuel takes place. It is the bright part of the flame.
• The innermost zone of the flame is the least hot and is black in colour. This is due to the presence of unburnt wax vapours.

Smoke

• Smoke is an example of solid (unburnt particles) dispersed in a gas (air).
• The black colour of the smoke is due to the presence of unburnt carbon particles in the smoke.

Types of Combustion

• The type of combustion in which heat and light are released in a very short span of time is called rapid combustion. For e.g. combustion of L.P.G.
• The type of combustion in which substances catch fire on their own, without the application of heat is termed as spontaneous combustion, for example, forest fires.

Working of a Matchstick

• The main component of the bulb of a matchstick is red phosphorus which turns into white phosphorus on heating.
• White phosphorus spontaneously ignites, thereby increasing the temperature of the wooden stem to the ignition point and the matchstick starts burning.

Fire Extinguisher

Fire Control

Fire can be controlled by removing any or all of the factors of combustion, i.e. fuel, oxygen (air) and ignition temperature (by lowering the temperature).

Fire Extinguisher

• The fire extinguisher is a device used by the fire brigade to control fire.
• The role of the fire extinguishers is to cut off the supply of oxygen or bring down the temperature of the fuel, or both.

Calorific Value

Ideal Fuel

• The ideal fuel is cheap, easily available and readily combustible.
• It has a high calorific value.
• It does not produce harmful gases or residues that pollute the environment.

Calorific Value and Efficiency of a Fuel

• The amount of heat energy produced on the complete combustion of 1 kg of a fuel is called its calorific value. The calorific value of a fuel is expressed in a unit called kilojoule per kg (kJ/kg).
• Efficiency is the proportion of energy released by a fuel combustion process which is converted into useful work.
• Calorific value is directly proportional to its efficiency. If the value is high, its efficiency will also be high. If the value is low, its efficiency would also be low.

Pollution

Harmful Products from Burning of Fuel

• The burning of fuels like wood, coal and petroleum products releases unburnt carbon particles in the air, which causes respiratory problems.
• The incomplete combustion of fuels produces a very poisonous gas called carbon monoxide.
• The burning of fuels releases carbon dioxide into the air in the environment, which causes global warming.

Unburnt Carbon Particles

• Carbon fuels like wood, coal, candle, and petroleum release unburnt carbon particles.
• These fine particles are dangerous pollutants causing respiratory diseases, such as asthma.

CO Emission

• Carbon monoxide is a poisonous gas which is produced by incomplete combustion of fuels.
• It is dangerous to burn coal in a closed room as the carbon monoxide produced can kill people sleeping in that room.

Global Warming

• The rise in the average temperature of the earth’s atmosphere due to the release of carbon dioxide on combustion of fuels is termed global warming.
• Melting of polar ice caps or change in the rainfall pattern are the consequences of global warming.

Acid Rain

• Acid rains are caused by emissions of sulphur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acid.
• It has a very harmful effect on plants, land and aquatic animals and infrastructure.

CNG – The Clean Fuel

The use of diesel and petrol as fuels in automobiles is being replaced by CNG (Compressed Natural Gas) because it is less polluting and cleaner fuel.

About ANAND CLASSES

Understanding the principles of combustion and flame is essential for students aspiring to excel in the Sainik School entrance exam. ANAND CLASSES, a leading coaching center in Jalandhar, led by esteemed faculty Er. Neeraj Anand, provides comprehensive study material notes tailored specifically for students preparing for the Sainik School exam. These notes aim to elucidate the science behind combustion and flame, empowering students to grasp the concepts with clarity and precision.

Unraveling the Science of Combustion and Flame:

The study material notes delve into the fascinating world of combustion and flame, covering topics such as the combustion process, types of flames, combustion reactions, and fire safety measures.

Key Features of ANAND CLASSES' Study Material:

1. Understanding Combustion: Students learn about the process of combustion, including its definition, conditions necessary for combustion, and factors influencing the rate of combustion. The study material notes provide a detailed explanation of the combustion process, from ignition to flame propagation.

2. Types of Flames: ANAND CLASSES' study material explores the different types of flames, including luminous and non-luminous flames, and their characteristics. Students gain insights into the properties of each type of flame and their applications in everyday life.

3. Combustion Reactions: The study material notes elucidate the chemical reactions involved in combustion, focusing on the oxidation of fuels and the release of heat and light energy. Students learn about the role of oxygen, fuel, and heat in combustion reactions, as well as the products formed during combustion.

4. Fire Safety Measures: ANAND CLASSES' study material emphasizes the importance of fire safety and provides valuable information on fire prevention, firefighting techniques, and emergency procedures. Students gain awareness of fire hazards and learn how to respond effectively to fire-related emergencies.

5. Practice Questions and Exercises: The study material includes a variety of practice questions and exercises designed to test students' understanding of the concepts covered. These questions are aligned with the exam pattern and format, helping students prepare effectively for the Sainik School entrance exam.

Faculty Expertise:

Er. Neeraj Anand, with his extensive experience and expertise in teaching science and technology, leads ANAND CLASSES' faculty team in providing high-quality education and guidance to students. His dedication to student success and deep understanding of the subject matter make ANAND CLASSES a trusted choice for Sainik School exam preparation.

Frequently Asked Questions Science - Combustion and Flames

Q1

What are the types of fire extinguishers?

The six main types of fire extinguishers are water, foam, carbon dioxide, powder, water mist and wet chemical.

Q2

What are some of the few ‘Inflammable’ substances?

Petrol, diesel, alcohol, and liquified petroleum gas (LPG) are some of the inflammable substances.

Q3

What are the elements present in a fire triangle?

Oxygen, Heat and fuel are the elements of the Fire Triangle.