1.compare and contrast the rate of solution formation between the three physical forms of salt that were placed in the vial and not agitated with the three forms of salt that were placed in the vial and were agitated.
2. on the basis of your results, what is the relationship between the temperature of the solvent and the rate of solution formation?
3. use your knowledge of collision theory to explain the results of your experiments in this laboratory.

The stable form of salt at standard temperature and pressure is solid. If you add water to salt, it will dissolve. However, there are certain factors that affect the rate of solution formation of salt. The rate of formation of salt solution is faster when the vial is agitated than when it is not agitated. By agitating the solution, you are increasing the surface area of the salt particles in contact with water.

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 think   the answer is c hope i'm right