Import Question JSON

Current Question (ID: 18081)

Question:

$\text{If 8 g of a non-electrolyte solute is dissolved in 114 g of n-octane to reduce its vapor pressure to 80\%, the molar mass (in g mol}^{-1}\text{) of the solute is:}$ $[\text{Molar mass of n-octane is 114 g mol}^{-1}]$

Options:

1. $40$
2. $60$
3. $80$
4. $20$

Solution:

$\text{Hint: } \frac{P^0 - P_s}{P^0} = X_{\text{solute}}$ $\text{Step 1:}$ $\text{Since moles of solute is very low, so it is a dilute solution,}$ $\frac{P^0 - P_s}{P^0} = \frac{n_{\text{solute}}}{n_{\text{solvent}}}$ $\text{Step 2:}$ $\text{Let } P^0 = 100, \text{ V.P reduced to 80\%, } \therefore P_s = 80$ $\frac{100 - 80}{100} = \frac{8/m}{114/114}$ $m = 40$

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
}