A rock is definitely more dense. If you were to put a cloud in water it would float/stay above it and a rock would sink to the bottom
I think i found your answers
Answer:
The air molecules that are surrounding the metal will speed up, and the molecules in the metal will slow down.
Explanation:
As molecules heat they begin to move faster. The heat from the metal plate will make the molecules at room temperature move faster. And the room temperature makes the hot place cool, making the hot plate molecules slow down.
To visualize this, you can use this link
https://phet.colorado.edu/en/simulations/gas-properties
click the play button to activate the activity
