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प्रश्न
The substance expected to have the highest ignition temperature out of the following is
पर्याय
kerosene
petrol
coal
alcohol
उत्तर
coal
Explanation -
Coal has the highest ignition temperature.
Note - The lowest temperature at which a substance catches fire and starts burning, is called its ignition temperature. Kerosene, petrol and alcohol have low ignition temperature.
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संबंधित प्रश्न
Give reasons.
Paper by itself catches fire easily whereas a piece of paper wrapped around an aluminium pipe does not.
True or False – If False give the correct answer
Oxygen is necessary for combustion
A substance which reacts with oxygen giving heat is called a combustible substance. Which one of the following is a combustible substance?
Two glass jars A and B are filled with carbon dioxide and oxygen gases respectively. In each jar, a lighted candle is placed simultaneously. In which jar, will the candle remain lighted for a longer time and why?
Match the items of Column A with the items of Column B.
| Column A | Column B |
| (a) Oxides of sulphur and nitrogen | (i) fire extinguisher |
| (b) CNG | (ii) incomplete combustion of coal |
| (c) Oxygen | (iii) very low ignition temperature |
| (d) inflammable substance | (iv) acid rain |
| (e) carbon dioxide | (v) necessary for combustion |
| (f) carbon monoxide | (vi) fuel for automobiles |
Complete the crossword with the help of the clues.
Across
1. Non-metal which catches fire if exposed to air. (10)
3. The lowest temperature at which a substance catches fire is called its ______ temperature. (8)
5. The most common fire extinguisher. (5)
Down
2. A chemical process in which a substance reacts with oxygen to give off heat. (10)
4. Petrol is used as a ______ in automobiles. (4)
6. It is as hard as stone and black in colour. (4)
The chemical process in which a substance reacts with oxygen to produce heat is called ______.
Complete combustion of the fuel takes place and the colour of the flame is yellow and is the hottest part of the flame.
Give one example of spontaneous combustion.
What do you mean by inflammable substance?
