Reactivity of organic halides with AgNO3 depends on C-X bond lability

Steps:

• Silver nitrate test detects halides by forming AgX precipitate upon C-X bond cleavage.
• Reaction proceeds via SN1 mechanism where Ag+ assists halide ionization.
• Reactivity order: tertiary > secondary > primary > aryl halides due to carbocation stability.
• Tertiary halides ionize fastest, producing precipitate quickest.

Why C is correct:

• (CH3)3CCl forms stable tertiary carbocation, enabling rapid SN1 reaction per Markovnikov's stability rule.

Why the others are wrong:

• A: CH3CH2Cl is primary, reacts slowly via SN2 mechanism.
• B: (CH3)2CHCl is secondary, forms less stable carbocation than tertiary.
• D: PhCl is aryl halide; C-Cl bond resists ionization due to resonance stabilization.

Final answer: C