What is the pressure exerted by a mixture of gases in a 10.0 L container at 65.0oC if the mixture contains 0.400 mol O2, 0.800 mol CH4, and 0.300 mol SO2?

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.

c- cold periods in earth's history during which glaciers covered much of the surface.

explanation:

i think   the answer is c hope i'm right