Which answer correctly describes the amount of carbon dioxide produced? A)
1.2 x 1024 molecules of carbon dioxide are produced.
B)
2 moles of carbon dioxide are produced.
C)
6.02 x 1023 molecules of carbon dioxide are produced.
D)
28 grams of carbon dioxide are produced.

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.

a electronegativity decreases beacuse the size of nucleus is bigger.