Import Question JSON

Current Question (ID: 20866)

Question:

$\text{When 10 mL of an aqueous solution of } \text{Fe}^{2+} \text{ ions was titrated in the presence of dil } \text{H}_2\text{SO}_4 \text{ using diphenylamine indicator, 15 mL of 0.02 M solution of } \text{K}_2\text{Cr}_2\text{O}_7 \text{ was required to get the end point. The molarity of the solution containing } \text{Fe}^{2+} \text{ ions is } x \times 10^{-2} \text{M. The value of } x \text{ is: (Nearest integer)}$

Options:

1. $18$
2. $34$
3. $12$
4. $43$

Solution:

$\text{Hint: } N_1V_1 = N_2V_2$ $\text{Cr}_2\text{O}_7^{2-} + \text{Fe}^{2+} \rightarrow \text{Fe}^{3+} + \text{Cr}^{3+}$ $15 \text{ ml} \quad 10 \text{ ml}$ $0.1 \text{ M}$ $N_1 V_1 = N_2 V_2$ $15 \times 0.02 \times 6 = 10 \times M \times 1$ $M = \frac{15 \times 0.02 \times 6}{10} = 0.18 = 18 \times 10^{-2} \text{M}$

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
}