Answer:
I think it both physical & chemical change :')
At the constant temperatures the lighter the gas molecules, the faster the average velocity of the gas molecules.
Answer:
Both are similar concepts.
Sound is the vibration of air particles (compression and expansion) the can reach your ears. But you can have vibration being propagated in liquids and solids as well.
Some sounds are generated in structures, so the vibration of a structure is converted to sound in air — for instance, a loudspeaker.
Explanation:
The answer is B particles combine into a large amount of engery.
