NTA Abhyas NEET2020ChemistryChemical KineticsPractice
Under what conditions a bimolecular reaction may be kinetically of first order?
Options
- AWhen both reactants have same concentration
- BWhen one of the reacting species is in large excess
- CWhen the reaction is at equilibrium
- DWhen the activation energy of reaction is less
Correct answer
B. When one of the reacting species is in large excess
Step-by-step solution
If one of the reacting species is in excess, a bimolecular reaction becomes first order reaction. It is generally called as pseudo unimolecular reaction e.g., R C O O R ' + H 2 O → R C O O H + R ' O H Here rate = K [ R C O O R ' ] 1 Here water is in excess so it is neglected.