The decomposition of dinitrogen monoxide (N2O\text{N}_2\text{O}N2O) on a hot gold surface is zero-order with respect to the reactant:
Rate=k \text{Rate} = k Rate=kWhich of the concentration–time graphs represents the variation in the concentration of N2O\text{N}_2\text{O}N2O as this reaction proceeds?

Graph B
Graph A
Graph C
Graph D