Import Question JSON

Current Question (ID: 18255)

Question:

$\text{If an iron rod is dipped in } \text{CuSO}_4 \text{ solution, then:}$ $1. \text{Blue colour of the solution turns red.}$ $2. \text{Brown layer is deposited on iron rod.}$ $3. \text{No change occurs in the colour of the solution.}$ $4. \text{None of the above.}$

Options:

1. $\text{Blue colour of the solution turns red.}$
2. $\text{Brown layer is deposited on iron rod.}$
3. $\text{No change occurs in the colour of the solution.}$
4. $\text{None of the above.}$

Solution:

$\text{HINT: Iron is more reactive than copper and so iron displaces copper from } \text{CuSO}_4 \text{ solution.}$ $\text{Explanation:}$ $\text{The oxidation potential value is as follows:}$ $\text{Fe/Fe}^{+2} = 0.44 \text{ eV}$ $\text{Cu/Cu}^{+2} = -0.33 \text{ eV}$ $\text{CuSO}_4 \text{ (blue)} + \text{Fe} \rightarrow \text{FeSO}_4 \text{ (light)} + \text{Cu (green)}$ $\text{Iron is more reactive than copper and so iron displaces copper from } \text{CuSO}_4 \text{ solution and a brown layer is deposited on an iron rod.}$

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
}