This quiz works best with JavaScript enabled. Home > Cbse > Class 8 > Science > Combustion And Flame > Class 8 Science Chapter 6 Combustion And Flame – Quiz 2 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 8 Science Chapter 6 Combustion And Flame Quiz 2 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. A combustible substance cannot catch fire or burn as long as its temperature is higher than its ignition temperature. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 2. The hottest part of the flame A) Inner part. B) Lower part. C) Outer part. D) Middle part. Show Answer Correct Answer: C) Outer part. 3. Combustion always results as flames A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 4. Substance that does not burn in air is A) Sand. B) Kerosene. C) Wood. D) Diesel. Show Answer Correct Answer: A) Sand. 5. When water is poured over burning wood, the fire goes off. This is because A) Molecules of water reacts with oxygen present in the flame. B) Temperature of water goes up. C) Temperature of wood decreases. D) The flame vapourises. Show Answer Correct Answer: C) Temperature of wood decreases. 6. Unburnt carbon particles of the fuel cause A) Stomach infections. B) Respiratory problems. C) Brain infections. D) Skin problems. Show Answer Correct Answer: B) Respiratory problems. 7. A fuel gives yellow flame due to A) Incomplete combustion. B) Spontaneous combustion. C) Rapid combustion. D) Complete combustion. Show Answer Correct Answer: A) Incomplete combustion. 8. Increased concentration of Carbon dioxide in the air causes ..... A) Forest fires. B) Global warming. C) Acid rain. D) None of the above. Show Answer Correct Answer: B) Global warming. 9. During the process of Combustion ..... is given out A) Heat. B) Light. C) Sound. D) All of these. Show Answer Correct Answer: D) All of these. 10. The non-luminous zone of the flame is the innermost zone which is used by goldsmiths for melting gold and silver. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 11. Are the molecules in wood the same as ash A) Depends. B) Yes. C) No. D) Does it matter. Show Answer Correct Answer: C) No. 12. The hottest zone in the candle flame is A) Non luminous zone. B) Luminous zone. C) Invisible zone. D) All zones are equally hot. Show Answer Correct Answer: A) Non luminous zone. 13. Combustion is a ..... A) Physical process. B) Chemical process. C) Both of these processes. D) None of these. Show Answer Correct Answer: B) Chemical process. 14. One of the following is not a combustible substance. The substance is: A) Chaff. B) Alcohol. C) Asbestos. D) Hydrogen. Show Answer Correct Answer: C) Asbestos. 15. The zone that produces yellow light in the candle flame is A) Nonluminous zone. B) Luminous zone. C) Invisible zone. D) All zone gives light. Show Answer Correct Answer: B) Luminous zone. 16. Which one of the following is combustible? A) Paper. B) Glass. C) Iron nail. D) Stone pieces. Show Answer Correct Answer: A) Paper. 17. Bitumen is used in A) Natural gas. B) Road surfacing. C) Coal tar. D) Electric generators. Show Answer Correct Answer: B) Road surfacing. 18. What is the process of burning substances in the presence of oxygen to produce heat and light? A) Breath. B) Vaporization. C) Combustion. D) Restoration. Show Answer Correct Answer: C) Combustion. 19. The products of combustion of a hydrocarbon are: A) Carbon + water. B) Carbon dioxide + water. C) Carbon dioxide + hydrogen. D) Hydrogen + oxygen. Show Answer Correct Answer: B) Carbon dioxide + water. 20. Which zone represents the partial combustion in candle flame? A) Middle zone. B) Inner zone. C) Lower zone. D) Outer zone. Show Answer Correct Answer: A) Middle zone. 21. Incomplete combustion of fuel in a furnace is judged by high ..... of the flue gases. A) DEW POINT. B) CO CONTENT. C) O2 CONTENT. D) CO2 CONTENT. Show Answer Correct Answer: B) CO CONTENT. 22. When magnesium ribbon is burnt, it produces ..... A) Magnesium sulphate. B) Magnesium chloride. C) Magnesium oxide. D) Magnesium hydroxide. Show Answer Correct Answer: C) Magnesium oxide. 23. Which of the following is not a byproduct of combustion of hydrocarbons? A) Carbon dioxide. B) Water. C) Oxygenation. D) Carbon. Show Answer Correct Answer: B) Water. 24. Which of the following statements are true?1. Yellow flames are ideal for heating2. The substances which vaporise during burning gives flames3. Luminous zone contains unburnt carbon particles4. The non-luminous zone has the highest temperature A) 1, 2 and 3. B) 1, 2 and 4. C) 2, 3 and 4. D) 1, 3 and 4. Show Answer Correct Answer: C) 2, 3 and 4. 25. What is the role of oxygen in the combustion process? A) Oxygen is used to extinguish fires. B) Oxygen acts as an oxidizer that enables the combustion of fuel. C) Oxygen cools down the combustion process. D) Oxygen is a byproduct of combustion. Show Answer Correct Answer: B) Oxygen acts as an oxidizer that enables the combustion of fuel. 26. Calculate the maximum theoretical temperature (t) attained when hydrogen is burnt in oxygen. The heat of combustion of hydrogen to water vapour is 57.8 Kcals. The specific heat of water vapour is [ 0.463 + 6.2x 10$^{-5}$t] t cals/g. A) 4308$^{0}$C. B) 4480$^{0}$C. C) 4580$^{0}$ C. D) 4380$^{0}$C. Show Answer Correct Answer: A) 4308$^{0}$C. 27. Which element shows spontaneous combustion A) Phosphorus. B) Calcium. C) Copper. D) Iron. Show Answer Correct Answer: A) Phosphorus. 28. Like fuel the sun also provides heat and light. the process taking place in the sun is called A) Combustion. B) Nuclear Reaction. C) Burning. D) None of these. Show Answer Correct Answer: B) Nuclear Reaction. 29. Combustion is a ..... process A) Physical. B) There is no process involved in the process of combustion. C) Chemical. D) Both. Show Answer Correct Answer: C) Chemical. 30. Why do we use paper or kerosene oil to start fire in wood or coal A) To reach ignition temperature of wood or coal by burning of paper or kerosene oil. B) For spreading the fire. C) To supply more oxygen through kerosene. D) To give blue flame to the wood or coal. Show Answer Correct Answer: A) To reach ignition temperature of wood or coal by burning of paper or kerosene oil. 31. Which is the hottest part of a flame A) Outer. B) Lower. C) Inner. D) Middle. Show Answer Correct Answer: A) Outer. 32. Fuel can be (understand and give the answer) A) Anything !!!!. B) Nothing !!!. C) Something !!!. D) Of solid liquid and gases. E) Helpful. Show Answer Correct Answer: D) Of solid liquid and gases. 33. Fuel formed under the earth's surface by the decomposition of organic matter is called A) Organic fuel. B) Biogas. C) Underground fuel. D) Fossil fuel. Show Answer Correct Answer: D) Fossil fuel. 34. The previously mentioned burning way or style is a type of combustion named as ..... Combustion. A) Rapid. B) Spontantaneous. C) Regular. D) None of These. Show Answer Correct Answer: B) Spontantaneous. 35. Complete combustion is when there is plenty of oxygen to react with. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 36. If a flame is giving off smoke, this type of combustion is occurring ..... A) Complete combustion. B) Incomplete combustion. C) All the above. D) None of the above. Show Answer Correct Answer: B) Incomplete combustion. 37. Which poisonous gas is formed as a result of incomplete combustion? A) Coal gas. B) Carbon monoxide. C) Carbon dioxide. D) Nitrogen oxide. Show Answer Correct Answer: B) Carbon monoxide. 38. What substance turns into gas and burns? A) Wick. B) Wax vapor. C) Solid wax. D) Hydrogen in the air. Show Answer Correct Answer: C) Solid wax. 39. Select the correct option which is suitable for the given below statement:The chemical used in mixture of modern matchsticks. A) Antimony trisulphide. B) Potassium bicarbonate. C) Sodium bicarbonate. D) None of the above. Show Answer Correct Answer: A) Antimony trisulphide. 40. Combustion reaction of fuels is a/an ..... reaction. A) AUTOCATALYTIC. B) EXOTHERMIC. C) ENDOTHERMIC. D) NONE OF THESE. Show Answer Correct Answer: B) EXOTHERMIC. 41. The gas helpful in combustion is A) Oxygen. B) Nitrogen. C) Hydrogen. D) Carbondioxide. Show Answer Correct Answer: A) Oxygen. 42. Name the chemical process in which a substance reacts with oxygen to give out heat. A) REACTION. B) JUNCTION. C) COMBUSTION. D) ALL OF THESE. Show Answer Correct Answer: C) COMBUSTION. 43. Bursting of crackers is an example of A) Rapid combustion. B) Spontaneous combustion. C) Explosion. D) All of these. Show Answer Correct Answer: C) Explosion. 44. Out of the following, Which of these are able to control fire A) Category. B) CO2. C) H2. D) NH3. Show Answer Correct Answer: B) CO2. 45. Burning of LPG is an example of ..... combustion. A) Spontaneous. B) Rapid. C) Explosion. D) Slow. Show Answer Correct Answer: B) Rapid. 46. Which is the hottest part in flame of candle? A) Wax part. B) Blue (outer). C) Yellow (middle). D) Black (inner). Show Answer Correct Answer: B) Blue (outer). 47. Moderately hot zone in a candle flame A) Outer zone. B) Middle zone. C) Innermost zone. D) Wax candle. Show Answer Correct Answer: B) Middle zone. 48. What is the color of the flame that burns when magnesium burns? A) Blue. B) White. C) Red. D) Yellow. Show Answer Correct Answer: B) White. 49. Ideal fuel has ..... calorific value A) Low. B) Zero. C) High. D) Moderate. Show Answer Correct Answer: C) High. 50. Burning of coal and diesel releases an extremely suffocating and corrosive gas called: A) Carbon dioxide. B) Sulphur dioxide. C) Oxides of Nitrogen. D) Hydrogen. Show Answer Correct Answer: B) Sulphur dioxide. 51. Calorific value is measured in A) Weight meter. B) Kilo joules per kg. C) Kilo joules. D) Kilo grams. Show Answer Correct Answer: B) Kilo joules per kg. 52. The sun produces heat and light by ..... A) Combustion. B) Nuclear Reaction. C) Burning. D) None of these. Show Answer Correct Answer: B) Nuclear Reaction. 53. Digestion of food is an example of A) Incomplete combustion. B) Complete combustion. C) Slow combustion. D) Rapid combustion. Show Answer Correct Answer: C) Slow combustion. 54. Match column 1 and column 2 and select the correct option from the given codes.Column 1 Column2P. Rusting i. ExplosionQ. Burning of paper ii. Spontaneous CombustionR. Sodium iii. Rapid CombustionS. Fire Crackers iv. Slow combustion A) P-ii, Q-iii, R-i, S-iv. B) P-iv, Q-iii, R-ii, S-i. C) P-iii, Q-iv, R-i, S-ii. D) P-i, Q-iii, R-ii, S-iv. Show Answer Correct Answer: B) P-iv, Q-iii, R-ii, S-i. 55. Which one of the following gases is used in combustion? A) CO. B) Oxygen. C) Nitrogen. D) Carbon dioxide. Show Answer Correct Answer: B) Oxygen. 56. Select the non combustible substance. A) Stone. B) Cloth. C) Paper. D) Dry leaves. Show Answer Correct Answer: A) Stone. 57. In which zone of the flame does complete combustion takes place? A) Middle zone. B) Inner zone. C) Outer zone. D) None of the above. Show Answer Correct Answer: C) Outer zone. 58. An ideal fuel is: A) Cheap, readily available. B) Having high calorific value. C) All of these. D) Rapidly combustible. Show Answer Correct Answer: C) All of these. 59. The acronym for putting out a fire using a fire extinguisher is PASS. What does PASS stands for A) Pul, accuracy, squeeze, spread. B) Pin, aim, squeeze, sweep. C) Pull, aim, squeeze, spread. D) Pull, aim, squeeze, sweep. Show Answer Correct Answer: D) Pull, aim, squeeze, sweep. 60. The outer zone of complete combustion is ..... in colour A) Black. B) Purple. C) Yellow. D) Orange. E) Blue. Show Answer Correct Answer: E) Blue. ← PreviousNext →Related QuizzesScience QuizzesClass 8 QuizzesClass 8 Science Chapter 6 Combustion And Flame Quiz 1Class 8 Science Chapter 6 Combustion And Flame Quiz 3Class 8 Science Chapter 6 Combustion And Flame Quiz 4 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books