Import Question JSON

Current Question (ID: 20784)

Question:

$\text{What is the molality of a solution containing 20\% (mass/mass) KI in water?}$ $\text{(molar mass of KI = 166 g mol}^{-1}\text{)}$

Options:

1. $1.51$
2. $7.35$
3. $4.08$
4. $2.48$

Solution:

$\text{Hint: Formula of}$ \textit{molality} = \frac{\text{amount of solute}}{\text{molar mass of solute} \times \text{amount of solvent(kg)}}$ $\text{Step 1:}$ $\text{20\% w/w KI solution means 20 g KI present in 100 g of solution.}$ $\text{Hence, amount of solvent(water) is 80 g.}$ $\text{Hence, the formula of molality is as follows:}$ $\textit{molality} = \frac{\text{amount of solute}}{\text{molar mass of solute} \times \text{amount of solvent(kg)}}$ $\text{Step 2:}$ $\text{Calculate molality as follows:}$ $\textit{molality} = \frac{20 \times 1000}{166 \times 80}$ $= 1.51 \text{ m}$

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
}