Import Question JSON

Current Question (ID: 21026)

Question:

$\text{What is the difference between } \Delta H \text{ and } \Delta U \ (\Delta H - \Delta U) \text{ when the combustion of one mole of heptane(l) is carried out at a temperature T?}$

Options:

1. $3RT$
2. $4RT$
3. $-3RT$
4. $-4RT$

Solution:

$\text{Hint: Use the formula, that is, } \Delta H = \Delta U + \Delta n_g RT$ $\text{Step 1:}$ $\text{The combustion reaction of one mole of heptane is as follows:}$ $\text{C}_7\text{H}_{16(l)} + 11\text{O}_{2(g)} \rightarrow 7\text{CO}_{2(g)} + 8\text{H}_2\text{O}_{(l)}$ $\text{The relation between } \Delta H \text{ and } \Delta U \text{ is as follows:}$ $\Delta H = \Delta U + \Delta n_g RT$ $\text{The value of } \Delta n_g \text{ is as follows:}$ $\Delta n_g = n_p - n_r$ $= 7 - 11 = -4$ $\text{Step 2:}$ $\Delta H = \Delta U + \Delta n_g RT$ $\Delta H - \Delta U = -4RT$ $\text{Hence, option 4th is the correct answer.}$

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
}