In a presentation about measuring mass, one of your classmates states, "Two objects of the same size will always have the same mass.” Is this statement correct? Why or why not?

Two objects of the same size will not have the same mass.

Explanation:

Mass is the amount of the matter present in an object.

If the size and shape differs then the mass in that object will also differ.

For example, if we take 2 balls of the same size namely one plastic ball and other one rubber ball.

Both the balls are of same size, but the mass present in plastic ball is lesser when compared to the rubber ball.

So rubber ball has more mass than the plastic ball, and so it is concluded that two objects of the same size will not always have the same mass.

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.