Questions to Ask Ask the children to compare the bag before and after it has been inflated. Our exhaled breath has water vapor in it. When our moist breath enters the bag, the water molecules condense on the inside of the bag.
Air takes up space, can hold things up and make things move.
That means that every square inch of your body, the top bottom and sides of a table, the walls of your house, etc. has 14.7 pounds of air pressure pushing on it. Why To explore the amazing things air can do To observe the water vapor present in our exhaled breath. What to Do Place the straw halfway in the bag. Zip the bag tightly around the straw. Blow into the straw.