Think back to what you learned from "Stargazing" about the size of the sun and its distance from Earth. Then reread the sentences above from "The Brightest Sky." Pay special attention to how the sentences describe the "red ball" that Emine sees. What might the "red ball" be? Support your answer with evidence from both "Stargazing" and "The Brightest Sky."

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.

level 4 to level 2 : ))