Final answer:
When collecting a gas over water, you can use a technique called water displacement. This involves capturing the gas in a bottle that has been filled with water and inverted into a dish filled with water. As the gas is produced, it exits through a tube and displaces the water in the bottle.
Step-by-step explanation:
When collecting a gas over water, you can use a technique called water displacement. This involves capturing the gas in a bottle that has been filled with water and inverted into a dish filled with water. As the gas is produced, it exits through a tube and displaces the water in the bottle.
For example, in a laboratory experiment, a reaction flask is fitted with rubber tubing and placed under the bottle of water. As the gas is produced in the reaction, it exits through the tubing and displaces the water in the bottle. When the bottle is full of the gas, it can be sealed with a lid.