In osmosis: a. Knowing the osmotic pressure can help determine the molar mass of a solute dissolved in a solvent. b. The semipermeable membrane is used to change the freezing and melting points of a solution. c. Solutions cannot have identical osmotic pressures. d. Temperature does not affect the osmotic pressure of a solution. e. At least two of the above statements are correct.

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