How Hot And Cold Changes In A Balloon. Many people are a bit hesitant to buy a balloon trip because they think it will be very cold up there. The expanding gas blows up the balloon.
Cold air is denser so it doesn’t rise to the same extent as hot air, which is how the hot air balloon gets lift. How hot and cold water changes a balloon? You won't believe your eyes as you attach a balloon to an empty bottle and place it in hot water!