Import Question JSON

Current Question (ID: 8279)

Question:

$\text{Select the correct option based on statements below:}$ $\begin{array}{|l|l|} \hline \text{Assertion (A):} & \text{C}_{\text{diamond}} \rightarrow \text{C}_{\text{graphite}} \text{ } \Delta H \text{ and } \Delta U \text{ are the same for this reaction.} \\ \hline \text{Reason (R):} & \text{Entropy increases during the conversion of diamond to graphite.} \\ \hline \end{array}$

Options:

1. $\text{Both (A) and (R) are true and (R) is the correct explanation of (A).}$
2. $\text{Both (A) and (R) are true but (R) is not the correct explanation of (A).}$
3. $\text{(A) is true but (R) is false.}$
4. $\text{Both (A) and (R) are false.}$

Solution:

$\text{Hint: Entropy increases during the conversion of diamond to graphite.}$ $\text{Consider the reaction,}$ $\text{C}_{\text{diamond}} \rightarrow \text{C}_{\text{graphite}}$ $\text{For the above reaction, } \Delta H \text{ and } \Delta U \text{ are same for this reaction. Entropy increases during the conversion of diamond to graphite because of diamond's compact crystal lattice than graphite. Hence, randomness is less.}$ $\text{Thus, both Assertion \& Reason are true but the reason is not the correct explanation of the assertion.}$ $\text{The assertion states that } \Delta H = \Delta U \text{ for this reaction. This is true because the reaction involves only solid phases with no change in the number of gas molecules (} \Delta n_g = 0 \text{). According to the relationship } \Delta H = \Delta U + \Delta n_g RT\text{, when } \Delta n_g = 0\text{, we get } \Delta H = \Delta U\text{.}$ $\text{While the reason correctly states that entropy increases during diamond to graphite conversion (due to the less ordered structure of graphite compared to diamond), this fact does not explain why } \Delta H \text{ equals } \Delta U\text{. The equality of } \Delta H \text{ and } \Delta U \text{ is due to the absence of gaseous molecules in the reaction, not because of entropy changes.}$

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
}