Import Question JSON

Current Question (ID: 8283)

Question:

$\text{2.1 g of Fe combines with S evolving 3.77 kJ. The heat of formation of FeS in kJ/mole is-}$

Options:

1. $- 3.77$
2. $- 1.79$
3. $- 100.5$
4. $\text{None of the above}$

Solution:

$\text{Hint: Heat of formation: The amount of heat absorbed or evolved when one mole of a compound is formed from its constituent elements}$ $\text{Calculate the mole of Fe}$ $\text{From } \text{Fe} + \text{S} \rightarrow \text{FeS}$ $\text{1 mol 1 mol } \quad \text{1 mol}$ $\frac{2.1}{56} \text{ a mole of Fe} = 0.0375 \text{ mol of Fe and FeS}$ $\text{Step 2:}$ $\text{Calculate the heat of formation of FeS as follows:}$ $\text{For } 0.0375 \text{ mol of FeS, heat of formation} = -3.77 \text{ kJ}$ $\text{For 1 mol of FeS, the heat of formation} = -\frac{3.77}{0.0375} = -100.5 \text{ kJ/mol}$ $\text{The negative sign indicates that heat is evolved (exothermic reaction) when FeS is formed from its elements.}$ $\text{Therefore, the heat of formation of FeS is -100.5 kJ/mol.}$

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
}