In the atmosphere, under the effect of ultraviolet rays, oxygen molecules combine to form ozone molecules, and ozone molecules also photodissociate to form oxygen molecules. which of the following would be observed if this reaction is in dynamic equilibrium? the concentration of oxygen will increase. the concentration of ozone will decrease. the rates of the forward and reverse reactions will increase. the rates of the forward and reverse reactions will remain the same.

The dynamic equilibrium only exists when a reversible reaction stops to change its ratio between reactants or products, however the substances move between the chemicals at an equal rate, which has no net change.

So here, the oxygen molecules in presence of ultraviolet rays forms ozone molecules.

in presence of UV rays. Hence the rates of the forward and backward reactions remains the same in the atmosphere even after photo dissociation.

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.