Atoms that are sp^2 hybridized can form pi bond(s). b. 2

True

Explanation:

Pi bonds are formed using p orbitals. Atoms that have p orbitals have 3 of them. In an sp² hybridized atom, only 2 of the 3 p orbitals are being used in the sp² orbitals, leaving one p orbital free for pi bonding. Therefore, only one pi bond can be formed to an sp² hybridized atom.

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.