Which observation indicates that a chemical reaction has taken place? O A substance becomes warmer.
O A material changes from a solid to liquid.
O Bubbles form when a liquid is heated.
O A new chemical substance is formed.

How is energy related to the change of state represented by the model? atoms gain energy as a solid changes to a liquid. atoms gain energy as a solid changes to a gas. atoms lose energy as a solid changes to a liquid. atoms lose energy as a solid changes to a gas.