The decomposition of NH3 on platinum surface is zero order reaction.
What are the rates of production of N2 and H2. if k = 2.5 × 10-4 mol L-1 sec-1?
2NH3(g) → N2(g) + 3H2(g)
Rate of zero order reaction is equal to rate constant. i.e. Rate = 2.5 × 10-4mol L-1sec-1.
According to rate law, 
2.5 × 10-4mol L-1sec-1 = 
i.e. the rate of production of N2 is 2.5 × 10-4mol L-1 sec-1.
According to rate law,
i.e. rate of formation of H2 is 3 times rate of reaction = 3 × 2.5 × 10-4mol L-1sec-1
= 7.5 × 10-4mol L-1sec-1
Rate of formation of N2 and H2 is 2.5 × 10-4 mol L-1sec-1 and 7.5 × 10-4 mol L-1sec-1 respectively.
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