Usha took a lump of dry soil in a glass and added water to it till it was completely immersed. She observed bubbles coming out. The bubbles contain
Question 8
a) Water vapour
b) Only oxygen gas
c) Air
d) None of these
Bubbles coming out of a lump of soil when water is poured on it represent ___.
Paheli kept some water in a beaker for heating. She observed that tiny bubbles appeared before the water started to boil. She boiled the water for about 5 minutes and filled it in a bottle up to the brim and kept the bottle airtight till it cooled down to room temperature. (a) Why did the tiny bubbles appeared? (b) Do you think tiny bubbles will appear on heating the water taken out from the bottle? Justify your answer
An experiment was performed to know about the source of air for the aquatic organisms. The experiment was as follows:
Take some water in a glass vessel. Heat it slowly on a tripod stand. Before the water begins to boil, look carefully at the inner surface of the vessel. Observe the bubbles that are coming up. Where are these bubbles coming from?