Question

consider the reaction and its energy diagram
2 a + 25 kcal/mol ↔ 2 b + c
true or false questions
1 the highest energy designated by the star * is called the transition state
2 the reactants and the products are electronically stable since they meet the
octet and duet rules
3 the transition state is when bonds to be broken are half - broken, and bonds to
be formed are half - formed
4 the octet and duet rules are met in the transition state
a. true b. false

Explanation:

Question 1:

Step1: Recall transition state definition

The transition state in a reaction energy diagram is the highest - energy point, representing the unstable intermediate where old bonds are breaking and new bonds are forming.

Step2: Compare with the diagram

The star * marks the highest energy point in the energy diagram, which fits the definition of the transition state.

Step1: Recall octet/duet rules

The octet rule (atoms tend to have 8 valence electrons) and duet rule (for H, 2 valence electrons) are related to the electronic stability of atoms in molecules. Reactants and products are stable species (not transition states), so they should follow these rules for stability.

Step2: Analyze the reaction context

Since reactants and products are the stable start and end points of the reaction (unlike the transition state), they meet octet/duet rules for stability.

Step1: Recall transition state bond behavior

By definition, in the transition state, the bonds that are going to be broken are in a partially - broken state, and the bonds that are going to be formed are in a partially - formed state (half - broken and half - formed).

Step2: Match with the statement

The statement accurately describes the bond - breaking and bond - forming nature of the transition state.

Answer:

A. true

Question 2: