Import Question JSON

Current Question (ID: 18488)

Question:

$\text{Native silver metal forms a water-soluble complex with a dilute aqueous solution of NaCN in the presence of:}$

Options:

1. $\text{Nitrogen}$
2. $\text{Oxygen}$
3. $\text{Carbon Dioxide}$
4. $\text{Argon}$

Solution:

$\text{HINT: It is in presence of oxygen.}$ $\text{Explanation:}$ $\text{STEP 1:}$ $\text{A water-soluble complex with silver and dilute aqueous solution of NaCN is } \text{Na[Ag(CN)}_2\text{]} \text{ in the cyanide process, the native silver is crushed and treated with aqueous NaCN solution and aerated.}$ $4\text{Ag} + 8\text{NaCN} + 2\text{H}_2\text{O} + \text{O}_2 \rightarrow 4\text{Na[Ag(CN)}_2\text{]} + 4\text{NaOH}$ $\text{STEP 2:}$ $\text{The cyanide process, also called Macarthur-Forrest Process, method of extracting silver and gold from their ores by dissolving them in a dilute solution of sodium cyanide or potassium cyanide.}$ $4\text{Au(s)} + 8\text{CN}^-\text{(aq)} + 2\text{H}_2\text{O(aq)} + \text{O}_2\text{(g)} \rightarrow 4[\text{Au(CN)}_2]^-\text{(aq)} + 4\text{OH}^-\text{(aq)}$ $2[\text{Au(CN)}_2]^- + \text{Zn(s)} \rightarrow [\text{Zn(CN)}_4]^{2-} + 2\text{Au(s)}$

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
}