Explain the identification process for a single replacement reaction and the factors that need to be considered.

A single-displacement reaction occurs when an element replaces another element in a compound. A metal only replaces a metal, and a nonmetal only replaces a nonmetal. Only a more reactive element can replace the other element in the compound with which it reacts.

can you attach a picture of the lettuce? : )

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.