6. Combustion And Flame Class 8 Science [LATEST] Solutions Additional Questions With Solutions in English - CBSE Study
NCERT Solutions for Class 8 Science are carefully prepared according to the latest CBSE syllabus and NCERT textbooks to help students understand every concept clearly. These solutions cover all important 6. Combustion And Flame with detailed explanations and step-by-step answers for better exam preparation. Each Additional Questions With Solutions is explained in simple language so that students can easily grasp the fundamentals and improve their academic performance. The study material is designed to support daily homework, revision practice, and final exam preparation for Class 8 students. With accurate answers, concept clarity, and structured content, these NCERT solutions help learners build confidence and score higher marks in their examinations. Whether you are revising a specific topic or preparing an entire chapter, this resource provides reliable and syllabus-based guidance for complete success in Science.
Class 8 English Medium Science All Chapters:
6. Combustion And Flame
5. Additional Questions With Solutions
Combustion And Flame:
Ques: What is combustion?
Ans: The chemical process in which a substance reacts with oxygen and gives heat is called combustion.
Ques: What is fuel?
Ans: The substance that undergoes combustion is said to be combustible. It is also called a fuel.
Ques: Name the reaction by which heat and light are produced in the sun.
Ans: Nuclear reaction.
Ques: What is ignition temperature?
Ans: The lowest temperature at which a substance catches fire is called its ignition temperature.
Ques: Why does the paper cup not burn while boiling water?
Ans: The heat supplied to the paper cup is transferred to water by conduction. So, in the presence of water, the ignition temperature of paper is not reached. Hence, it does not burn.
Ques: Write three essential requirements for producing fire.
Ans:
(i) Inflammable substance - fuels.
(ii) Ignition temperature
(iii) Oxygen
Ques: Which extinguisher is used to control the fire involving electric equipment and inflammable material like petrol?
Ans: CO2
Ques: How can fire be controlled suddenly?
Ans: The contact between fuel and oxygen is cut off to control the fire. For this, there are many processes like watering, use of CO2 . It also brings down the ignition temperature.
Ques: What is the advantages of use CO2 to control the fire.
Ans: CO2 does not harm the electric equipment while watering causes electric conduction.
Ques: Explain how CO2 is able to control fires?
Ans: CO2 being heavier than oxygen, covers the fire like blanket. Since the contact between the fuel and oxygen is cut off, the fire is controlled.
Ques: Write the types of combustion.
Ans: There are three types of combustion
(i) Rapid combustion
(ii) Spontaneous combustion.
(iii) Explosion.
Ques: The candle gives flame during burning but charcoal does do so. Why?
Ans: The substances which vaporize during burning, gives flames. The candle is vaporised but the charcoal is not vaporised.
Ques: What are the various zone of flame?
Ans: The various zone of flame:
(i) Dark zone
(ii) Luminous zone
(iii) Non – luminous zone
Ques: Which zone of a flame does a goldsmith use for melting gold and silver and why?
Ans: The goldsmith uses dark zone. Since it is the hottest part of flame.
Ques: What do you mean by calorif value? Write its units.
Ans: The amount of heat energy produced on complete combustion of 1 kg of a fuel is called its calorific value. Its unit is kilojoules per kg (kj/kg)
Ques: What is the main cause of global warming?
Ans: CO2
Ques:Which poisonous gas are given by incomplete combustion of fuels?
Ans: Carbon monoxide.
Topic Lists: