She boiled water in a can until steam has driven out the air present inside the can. She removed the can from the flame and placedthe stopper immediately. Then, cold water was poured over the can.What could have been her observation and what might be the reason for the change.
Answers
Answer:
A small amount of water is added to an aluminum soda can and brought to boiling on a hot plate or with a Bunsen burner. The water gas molecules will occupy all the space inside the can since the air molecules have been pushed out. The hot gas molecules are the same pressure as the air outside the can. When the can is placed in cold water upside down, the hot gas water molecules are cooled very rapidly. Some of the gas molecules are condensed back into liquid water so there are less molecules of water in the gas phase inside the can. The cold water will also cool any remaining gas molecules, decreasing their kinetic energy and therefore decreases the number of collisions with the walls of the can. This decreases the pressure inside the can. Since the air pressure outside the can is stronger than that inside the can, it causes the can to collapse.