Solids, liquids, and gases can be distinguished by their

The three states of matter are solid, liquid and gas phase. The solid has a more definite shape and volume. The particles are locked into place. It cannot be further compressed due to the bond that exists between the molecules. The kinetic energy of the molecules is close to none because the molecules are so close and so compact with each other. For liquids, it has a medium shape and volume. The particles can move or slide past each other due to the small space available for movement. It cannot be compressed further due to the repulsive forces that acts between them. The kinetic energy is medium. For gases, it has no shape and volume because the particles can move freely from one other. Their collisions are rare due to the distance between them. The kinetic energy of the molecules is high because there is room for movement. It can be compressed easily.

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.

i have no clue hope you find the answer