Consider the equilibrium c2h6(g)⇌c2h4(g)+h2(g). at 1000. k and a constant total pressure of 1.00 bar, c2h6(g) is introduced into a reaction vessel. the total pressure is held constant at 1 bar and at equilibrium the composition of the mixture in mole percent is h2(g): 26.6 %, c2h4(g): 26.6 %, and c2h6(g): 46.8 %.

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.

lol for the pointsss