Question

For the overall chemical reaction shown below, which one of the following statements can be rightly assumed?
2H₂S_(g) + O_2(g) --> 2S_(s) + 2H₂O_(l)

A) The reaction is third order overall

B) The reaction is second order overall

C) The rate law is, rate = k[H₂S]² [O₂].

D) The rate law is, rate = k[H₂S] [O₂].

E) The rate law cannot be determined from the information given.

Answer 1

By just seeing a particular reaction we cannot decide it's order. To decide the order we need to know each and every elemental reaction involved in the mechanism . Because we do not know how many reactants are actually participating in a chemical reaction . Also the order is an experimental data which can even be negative , decimal or even a whole number. Hence , It's just quite impossible to predict the order of a reaction , since rate law depends upon the order of a reaction with respect to each reactant but unfortunately when we do not know the order with respect to each reactant then we cannot determine the rate law too...