Ascientist investigates on two unknown solutions. which is not a scientific experiment she can perform on the solutions?
a) use a ph indicator to the test the solutions for acidity
b) heat the solutions and compare their boiling points
c) ask her coworkers which solution they think is better
d) put the solutions in a vacuum and measure their evaporation rates

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.

indium, and thallium have three electrons i think