Combustion and Flame
| Description: Combustion And Flame | |
| Number of Questions: 21 | |
| Created by: Sanjiv Memon | |
| Tags: Science Combustion and Flame Combustion, Types of Combustion Flame, Structure of a Flame. |
When a magnesium ribbon burns, it combines with the oxygen from the air to form _____________, liberating heat and light.
When charcoal burns, the carbon of the charcoal combines with the oxygen of the air to form
Which of the following statements is/are false? a. When charcoal burns with the oxygen in the air, a lot of heat, but only a little light is produced. b. Carbon dioxide is necessary for combustion to take place. c. Respiration is a kind of slow combustion of food which takes place to produce heat in the body.
Which of the following substances has the lowest ignition temperature?
Which of the following is/are the conditions necessary for combustion?
a. Presence of a combustible substance. b. Presence of a supporter of combustion. c. Heating of the combustible substance to its ignition temperature.
The fire produced by ___________ cannot be extinguished by water.
Which of the following has the highest ignition temperature?
Which of the following statements is/are false? a. The rust on iron is formed when iron combines with hydrogen to form iron oxide. b. Very little heat and no light is released in the process of rusting of iron. c. In the Sun, heat and light are produced due to nuclear reactions in which hydrogen is converted into helium.
Which of the following chemicals can be used to extinguish electric fire?
Which of the following statements is/are false? a. A combustible substance cannot catch fire as long as its temperature is higher than its ignition temperature. b. A supporter of combustion is necessary for the combustion to take place. c. The lowest temperature at which a substance catches fire and starts burning is called its ignition temperature.
Which of the following are used to make the head of matchsticks these days?
a. Antimony trisulphide b. Potassium chlorate c. Red phosphorus d. Brown sulphur
Which of the following gas is used to extinguish electric fires?
Which of the following is an example of explosive combustion?
Which of the following is/are ways to extinguish a fire?
a. By removing the fuel. b. By removing the heat. c. By cutting off the air supply to the burning substances.
Which of the following is not an example of a solid fuel?
Which of the following fuels has the highest calorific value?
Which of the following statements is/are false? a. Dry leaves catch fire easily, but green leaves do not. b. Coal fires cannot be started easily using a matchstick as coal has a high ignition temperature. c. The ignition temperature of wood is lower than that of kerosene.
Which of the following substances does not burn by producing a flame?
Which of the following statements is/are false? a. Different types of fuels produce different amounts of heat on burning. b. When water is thrown on a burning substance it gets cooled below its ignition temperature and stops burning. c. The amount of heat produced by the burning of one gram of a fuel is called its calorific value.
Match the following:
| a. Rapid combustion | 1. It is a very fast combustion reaction in which a large amount of heat, light and sound are produced. |
| b. Spontaneous combustion | 2. It is a combustion reaction which occurs on its own i.e. without the help of any external heat. |
| c. Explosive combustion | 3. It is a combustion reaction in which a large amount of heat and light are produced in a short time. |
Which of the following is not a characteristic of an ideal fuel?