Rank the following radicals in order of increasing stability,putting the least stable first.

Question

Quizplus · Accepted Answer

The stability of a radical is influenced by factors such as resonance, inductive effect, hyperconjugation, and steric hindrance. 
In radical I, there is no resonance or significant inductive effect to stabilize the radical. 
In radical II, there is resonance, which helps to delocalize the unpaired electron and stabilize the radical. 
In radical III, there are two resonance structures, both of which delocalize the unpaired electron and provide significant stabilization. Additionally, the tert-butyl group provides steric hindrance, which further stabilizes the radical. 
Therefore, the order of increasing stability is III < II < I.

Rank the Following Radicals in Order of Increasing Stability,putting the Least