A sample of pure NO2 is heated to 337 °C, at which temperature it partially dissociates according to the equation: 2 NO2( g) ∆ 2 NO( g) + O2( g) At equilibrium the density of the gas mixture is 0.520 g>L at 0.750 atm. Calculate Kc for the reaction.

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.

is there any options? maybe im just not seeing them but i need the options to

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