Import Question JSON

Current Question (ID: 21286)

Question:

$\text{Which one of the carbocations from the following is most stable?}$

Options:

1. $\overset{+}{\text{CH}_2} \text{CH} = \text{CH} - \text{O} - \text{CH}_3$
2. $\overset{+}{\text{CH}_2} \text{CH} = \text{CH} - \overset{\cdot}{\text{O}} - \text{CH}_3$
3. $\overset{+}{\text{CH}_2} \text{CH} = \text{CH} - \text{C} = \text{O} - \text{CH}_3$
4. $\overset{+}{\text{CH}_2} \text{CH} = \text{CH} - \text{F}$

Solution:

$\text{Hint: Carbocation intermediate is stabilized by +I, +M \& hyperconjugation effect.}$ $\text{The +M effect stabilizes carbocations by delocalizing the positive charge through resonance, particularly in systems with conjugated } \pi \text{ bonds or lone-pair donors.}$ $\text{While inductive effects can counteract this stabilization (e.g., in halogens), resonance generally dominates when conjugation is possible.}$ $\text{Since option 2 carbocation is in conjugation with stronger +M group } -\text{OCH}_3, \text{ it will be most stable.}$ $\text{Option 1: The carbocation is allylic and can be stabilized through resonance with the adjacent } \text{C=C bond and oxygen.}$ $\text{Option 2: The carbocation is allylic and next to an oxygen lone pair, providing strong resonance stabilization.}$ $\text{Option 3: The carbocation is allylic and conjugated with a carbonyl (C=O) group, which can participate in resonance but is less effective than oxygen directly donating electrons.}$ $\text{Option 4: The carbocation is allylic, but fluorine is an electronegative group, which has an -I effect (inductive withdrawal), making it less stable.}$ $\text{Hence, option 2 is the correct answer.}$

Import JSON File

Upload a JSON file containing LaTeX/MathJax formatted question, options, and solution.

Expected JSON Format:

{
  "question": "The mass of carbon present in 0.5 mole of $\\mathrm{K}_4[\\mathrm{Fe(CN)}_6]$ is:",
  "options": [
    {
      "id": 1,
      "text": "1.8 g"
    },
    {
      "id": 2,
      "text": "18 g"
    },
    {
      "id": 3,
      "text": "3.6 g"
    },
    {
      "id": 4,
      "text": "36 g"
    }
  ],
  "solution": "\\begin{align}\n&\\text{Hint: Mole concept}\\\\\n&1 \\text{ mole of } \\mathrm{K}_4[\\mathrm{Fe(CN)}_6] = 6 \\text{ moles of carbon atom}\\\\\n&0.5 \\text{ mole of } \\mathrm{K}_4[\\mathrm{Fe(CN)}_6] = 6 \\times 0.5 \\text{ mol} = 3 \\text{ mol}\\\\\n&1 \\text{ mol of carbon} = 12 \\text{ g}\\\\\n&3 \\text{ mol carbon} = 12 \\times 3 = 36 \\text{ g}\\\\\n&\\text{Hence, 36 g mass of carbon present in 0.5 mole of } \\mathrm{K}_4[\\mathrm{Fe(CN)}_6].\n\\end{align}",
  "correct_answer": 4
}