Import Question JSON

Current Question (ID: 18038)

Question:

$\text{The amount of benzoic acid (C}_6\text{H}_5\text{COOH) required for preparing 250 mL of 0.15 M solution in methanol is:}$

Options:

1. $4.57 \text{ g}$
2. $3.57 \text{ g}$
3. $1.57 \text{ g}$
4. $12.57 \text{ g}$

Solution:

$\text{Hint: The molarity (M) of a solution is the number of moles of solute dissolved in one liter of solution.}$ $\text{Explanation:}$ $0.15 \text{ M solution of benzoic acid in methanol means, 1000 mL of solution contains 0.15 mol of benzoic acid}$ $\text{Therefore, 250 mL of solution contains } = \frac{0.15 \times 250}{1000} \text{ mol of benzoic acid} = 0.0375 \text{ mol of benzoic acid}$ $\text{Molar mass of benzoic acid (C}_6\text{H}_5\text{COOH)} = 7 \times 12 + 6 \times 1 + 2 \times 16 = 122 \text{ g mol}^{-1}$ $\text{Hence, required benzoic acid} = 0.0375 \text{ mol} \times 122 \text{ g mol}^{-1} = 4.575 \text{ g}$

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
}