Right balanced chemical equations, complete ionic equations, and net ionic equations for the reactants below. Include a description of what you did while going through your solving. 1. HgI2+PbSO4

2. Sodium carbonate and calcium react in a single replacement, one of the resulting products immediately decomposes. (you should end up with one balanced equation - 3 product)

3. CaS + Al

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.