Import Question JSON

Current Question (ID: 10960)

Question:

$\text{The Prussian blue colour obtained during the test of nitrogen by Lassaigne's test is due to the formation of-}$

Options:

1. $\text{Fe}_4[\text{Fe}(\text{CN})_6]_3$ (Correct)
2. $\text{Na}_3[\text{Fe}(\text{CN})_6]$
3. $\text{Fe}(\text{CN})_3$
4. $\text{Na}_4[\text{Fe}(\text{CN})_5\text{NOS}]$

Solution:

$\text{Hint: Ferriferrocyanide is obtained as product.}$ $\text{The reaction takes place in Lassaigne's test are as follows:}$ $\text{Na} + \text{C} + \text{N} \rightarrow \text{NaCN}$ $6\text{NaCN} + \text{FeSO}_4 \rightarrow \text{Na}_4[\text{Fe}(\text{CN})_6] + \text{Na}_2\text{SO}_4$ $\text{Na}_4[\text{Fe}(\text{CN})_6] + \text{Fe}^{3+} \rightarrow \text{Fe}_4[\text{Fe}(\text{CN})_6]_3$ $\text{The final product Fe}_4[\text{Fe}(\text{CN})_6]_3 \text{ is known as ferriferrocyanide or Prussian blue, which gives the characteristic blue color in Lassaigne's test for nitrogen detection.}$

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
}