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Chemistry · 2026 · 2 marks
CBSE 2026 · Region 3 · Set 1 · Q18
For a reaction A + B → Products, the rate law is: Rate = k [ A ][ B ]^(3/2) Write the overall order of the reaction. Can this reaction be an…
For a reaction $\displaystyle \mathrm{A}+\mathrm{B} \rightarrow$ Products, the rate law is : \[\text { Rate }=\mathrm{k}[\mathrm{~A}][\mathrm{B}]^{\frac{3}{2}} \] Write the overall order of the reaction. Can this reaction be an elementary reaction? Give reason in support of your answer.
Marking-scheme solution
Overall order =$\displaystyle 5$/$\displaystyle 2$
No
Because for an elementary reaction order and molecularity are equal, but
molecularity can’t be fractional.
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