Advertisements
Advertisements
Question
You are provided with three watch glasses containing milk, petrol and mustard oil respectively. Suppose you bring a burning candle near these materials one by one, which material(s) will catch fire instantly and why?
Advertisements
Solution
The watch glass containing petrol will catch fire instantly because its ignition temperature is very low. Also, petrol is an inflammable substance, i.e. it can easily catch fire with a flame.
APPEARS IN
RELATED QUESTIONS
Make a labelled diagram of a candle flame.
Abida and Ramesh were doing an experiment in which water was to be heated in a beaker. Abida kept the beaker near the wick in the yellow part of the candle flame. Ramesh kept the beaker in the outermost part of the flame. Whose water will get heated in a shorter time?
True or False – If False give the correct answer
All fuels form flame.
Name the unit in which the calorific value of a fuel is expressed?
The ______ temperature at which a substance catches fire is called its ______ temperature.
Anu wants to boil water quickly in a test tube. On observing the different zones of the flame, she is not able to decide which zone of the flame will be best for boiling water quickly. Help her in this activity.
Match the following for the flame of a candle.
| Column A |
Column B |
Column C |
| (a) hottest part | (i) innermost zone of unburnt wax vapours | (x) blue |
| (b) moderately hot | (ii) middle zone of partial combustion | (y) black |
| (c) least hot | (iii) outer zone of complete combustion | (z) yellow |
Write True/False against the following statement and also correct the false statement.
Middle zone is the hottest zone of a flame.
Match the following:
| 1. | Inner zone | a. | Yellow |
| 2. | Outer zone | b. | Borax powder |
| 3. | Middle zone | c. | Blue |
| 4. | Green flame | d. | Black |
Write a note on flame.
