Question detail
Describe the relationship between the strength of the carbon-halogen bond and the rate of nucleophilic substitution reactions in halogenoalkanes.
Try the question, check the answer, then read the explanation to understand the curriculum point.
At a glance
Question
Type
exam_style
Style
Topic
Halogenoalkanes
Question
Describe the relationship between the strength of the carbon-halogen bond and the rate of nucleophilic substitution reactions in halogenoalkanes.
Answer
The strength of the carbon-halogen bond inversely affects the rate of nucleophilic substitution reactions. Weaker carbon-halogen bonds, which have lower bond enthalpy, break more readily, resulting in a faster reaction rate. Stronger bonds with higher enthalpy lead to slower reaction rates due to the increased energy required to break them.
Explanation
This answer effectively explains the inverse relationship between bond strength and reaction rate, reinforcing the concept of bond enthalpy in chemical reactions. It assesses the student's ability to articulate the impact of bond strength on reaction kinetics.
Common mistake
Misunderstanding Bond Enthalpy
Students often confuse bond enthalpy with bond strength, leading to incorrect conclusions about reaction rates.
To clarify, remember that bond enthalpy is the energy required to break a bond. Use the formula for reaction rate dependence on bond enthalpy: a lower bond enthalpy indicates a faster reaction rate. For example, if the carbon-bromine bond has a bond enthalpy of 285 kJ/mol and the carbon-chlorine bond has a bond enthalpy of 338 kJ/mol, the reaction involving the carbon-bromine bond will proceed faster due to lower energy required to break the bond. Thus, the reaction rate is influenced by bond enthalpy.
Related flashcards
Flashcard 1 of 5
Related practice questions
Question 1 of 5
Choose an answer, get feedback, then move sideways through the set.