A boy maintains a aquarium. On a cold day he put a small heater inside theaquarium to make water in it slightly warm. After a few hours, he found all the fish dead. What is the reason for it?
1. Like humans, fishes also need oxygen to breathe and stay alive.
2. Oxygen is more soluble in cold water, than hot water.
3. When he put a small heater in the aquarium, all the oxygen from the water was expelled out and fishes died due to absence of oxygen.