Complete Activity 4.5 (Page 47). Light a candle (Caution : Be careful). Hold a 4-5 cm long thin glass tube with a pair of tongs and introduce its one end in the dark zone of a non-flickering candle flame (Fig. 4.10). Bring a lighted matchstick near the other end of the glass tube. Do you see a flame caught at this end of the glass tube after a while? If so, what is it that produces a flame?
Answer:
The above activity can be carried out as follows:
Aim: To observe what happens when the lighted matchstick is brought near the other end of the glass tube and conclude based on that.
Materials Required: Candle, 4-5 cm long thin glass tube, matchstick.
Procedure:
(i) Light the candle.
(ii) Hold the glass tube with a pair of tongs and introduce its one end in the dark zone of the non-flickering candle flame.
(iii) Bring a lighted matchstick at the other end of the glass tube and observe what happens.
Observations:
You will observe a flame at the other end of the glass tube near which the matchstick is brought.
Conclusions:
We conclude that wax vapours coming out of the glass tube must have resulted in the flame when the matchstick was brought near the vapours. Therefore, it is proved that substances which vapourise on burning give flames.
“Light a candle (Caution : Be careful). Hold a 4-5 cm long thin glass tube with a pair of tongs and introduce its one end in the dark zone of a non-flickering candle flame (Fig. 4.10). Bring a lighted matchstick near the other end of the glass tube. Do you see a flame caught at this end of the glass tube after a while? If so, what is it that produces a flame?” – Solved.
Related Links:
Solution to Extended Learning Problem 1
Solution to Extended Learning Problem 2
Solution to Extended Learning Problem 3
Solution to Extended Learning Problem 4
Solution to Extended Learning Problem 5
Solution to Activity 4.1
Solution to Activity 4.2
Solution to Activity 4.3
Solution to Activity 4.4
