Import Question JSON

Current Question (ID: 18088)

Question:

$\text{A solution containing } 3.3 \text{ g of a substance in } 125 \text{ g of benzene (b.p. } 80^{\circ} \text{C) boils at } 80.66^{\circ} \text{C. If } K_b \text{ for one litre of benzene is } 3.28^{\circ} \text{C m}^{-1}, \text{ the molecular weight of the substance shall be -}$

Options:

1. $127.20 \text{ g mol}^{-1}$
2. $131.20 \text{ g mol}^{-1}$
3. $137.12 \text{ g mol}^{-1}$
4. $142.72 \text{ g mol}^{-1}$

Solution:

$\text{Hint: Elevation in boiling point}$ $\text{Explanation:}$ $\text{Step 1:}$ $\text{The formula of elevation in boiling point is as follows:}$ $T_b - T_b^0 = k_b \times m$ $T_b - T_b^0 = k_b \times \frac{\text{amount of substance}}{\text{molar mass of substance}} \times \frac{1000}{\text{amount of solvent}}$ $\text{Step 2:}$ $\text{Calculate the molar mass of the substance as follows:}$ $80.66 - 80 = 3.28 \times \frac{3.3}{\text{molar mass of substance}} \times \frac{1000}{125}$ $\text{molar mass of substance} = 131.2 \text{ g mol}^{-1}$

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
}