In a helium balloon- one that floats and rises to the ceiling it is elemental helium that is used to inflate the balloon. If you just blow into a balloon to inflate it then it is air inside the balloon which is a mixture of gases, principally nitrogen and oxygen (both elements). There are also other gases that are chemical compounds such as carbon dioxide.
The air inside a balloon is not a pure substance. However, it is a homogeneous mixture of gases which may include aluminum, magnesium and so much more.
The air inside a hot air balloon is the same as normal air around the balloon and the air you're breathing, only heated by the flame inside the balloon, hence HOT AIR balloon.
Natural air is always a mixture, and more or less homogenous in its major constituents. However, if the balloon was inflated by mouth, it will have less oxygen and more carbon dioxide than the air outside the balloon, which is also a mixture.
Air is not a pure substance.
D: The hot air inside the balloon becomes less dense than the air outside the balloon.
the air inside the balloon has more kinetic energy
No, I am sorry, but there is no helium inside a hot-air balloon. Instead, there is hot air.
D: The hot air inside the balloon becomes less dense than the air outside the balloon.
No. Air or helium goes inside the balloon.
For a balloon that is sealed and not full the volume of air inside the balloon will increase as it is heated. This is not however how hot air balloons work. A hot air balloon is essentially a fixed volume when it is inflated. If the air inside the balloon is heated the air inside becomes less dense so some of the air exits the balloon via the mouth of the balloon. As the air inside the balloon cools it becomes more dense so some air is ingested via the mouth of the balloon to keep it full. With each heating and cooling cycle, the pressure inside the balloon remains constant, the volume of the balloon remains constant but there is this movement of air out of and back into the balloon. P=VT Poop
The hot air inside the balloon expands, making the hot air balloon fly.
-- Inflate the balloon with some substance that is less dense than air. OR -- Inflate the balloon with air, then heat it after it is sealed.
A hot air balloon is called an hot air balloon because, the inside is heated up to make it less dense, allowing it to rise. Meaning, your heating up the air inside the balloon, hence, the name: Hot air balloon.