Read the passage carefully and answer the questions based on the passage:

The number of reacting species (atoms, ions or molecules) taking part in an elementary reaction, which must collide simultaneously in order to bring about a chemical reaction is called molecularity of a reaction. In the rate equation Rate = $k [A]^x [B]^y$

$x$ and $y$ indicate how sensitive the rate is to the change in concentration of A and B, respectively. Sum of these exponents, i.e., $x + y$ gives the overall order of a reaction where $x$ and $y$ represent the order with respect to the reactants A and B, respectively. Hence, the sum of powers of the concentration of the reactants in the rate law expression is called the order of that chemical reaction. For a first order reaction, the concentration of the reactant varies as $[R] = [R]_0e^{-kt}$

Which of the following statements is not true for order of a reaction?

Order of a reaction cannot be fraction.

The correct answer is Option (2) → Order of a reaction cannot be fraction.

The incorrect statement is: 2. Order of a reaction cannot be fraction.

Statement: A balanced chemical equation does not give the correct order of reaction every time.
Reason: This statement is true. The order of a reaction depends on the rate law, which is determined experimentally, not on the stoichiometric coefficients of the balanced chemical equation. Many reactions occur through complex mechanisms, so the balanced equation may not reflect the actual rate-determining steps.

Statement: Order of a reaction cannot be fraction.
Reason: This statement is false. The order of a reaction can be fractional, such as 1/2 or 3/2. Fractional orders arise in reactions involving complex mechanisms or intermediate species.

Statement: Order of a reaction can be determined experimentally only.
Reason: This statement is true. The order of a reaction is obtained from experimental data by studying how the reaction rate changes with reactant concentrations. It cannot be predicted accurately from the chemical equation alone.

Statement: Order of a reaction can be zero also.
Reason: This statement is true. In a zero-order reaction, the rate is independent of the concentration of the reactant. Such reactions are commonly observed in surface-catalyzed reactions or when a catalyst is saturated.