MHT CET Medical202626 April 2026Morning ShiftChemistryChemical KineticsActual
For the reaction C ₂ H ₅ Br _ (l) C ₂ H _ 4(g) + HBr , r = K( C ₂ H ₅ Br ) What is order and molecularity of the reaction respectively ?
Options
- A1, 2
- B2, 1
- C2, 2
- D1, 1
Correct answer
D. 1, 1
Step-by-step solution
The rate law is given as r = K[ C ₂ H ₅ Br ] . The order of a reaction is the sum of the exponents of the concentration terms in the rate law. Since the exponent of [ C ₂ H ₅ Br ] is 1 , the order of the reaction is 1 . The molecularity of an elementary reaction is the number of reactant molecules taking part in the reaction. In the given reaction, only one molecule of C ₂ H ₅ Br is reacting, so the molecularity is 1 . Thus, the order and molecularity are 1 and 1 respectively. Answer: 1, 1