Rate law expression cannot be determined from a balanced chemical equation if.

a.  The reverse reaction is involved

b.  It is an elementary reaction

c.  It is a sequence of elementary reactions

d.  Any of the reactants is in excess

The correct choice among the given is -

1. (a, b, c)

2. (b, c, d)

3. (a, c, d)

4. (a, b, d)

 

Hint: For elementary reaction balanced equation can be used to find rate of the reaction

Rate law can be determined from a balanced chemical equation if it is an elementary reaction. The rate law for a complex reaction find experimentally not from balanced equation.