Import Question JSON

Current Question (ID: 7426)

Question:

$\text{If 4 g of NaOH dissolves in 36 g of H}_2\text{O, the molarity of the solution is: (specific gravity of solution is 1 g mL}^{-1}\text{) :}$

Options:

1. $3 \text{ M}$
2. $3.5 \text{ M}$
3. $2.5 \text{ M}$
4. $2 \text{ M}$

Solution:

$\text{Hint: Use the formula of molarity that is, molarity} = \frac{\text{moles of solute}}{\text{volume of solution(mL)}} \times 1000$ $\text{Explanation:}$ $\text{Step 1: Number of moles of NaOH, n}_{\text{NaOH}} = \frac{4}{40} = 0.1 \text{ mol}$ $\text{Total mass of solution} = \text{mass of solute} + \text{mass of solvent}$ $= 4 + 36 = 40 \text{ g}$ $\text{Volume of solution} = \frac{\text{Mass of solution}}{\text{specific gravity}} = \frac{40 \text{ g}}{1 \text{ g mL}^{-1}} = 40 \text{ mL}$ $\text{Step 2:}$ $\text{Calculate the molarity of solution as follows:}$ $\text{Molarity} = \frac{\text{Moles of solute} \times 1000}{\text{Volume of solution (mL)}}$ $= \frac{0.1 \times 1000}{40} = 2.5 \text{ M}$ $\text{So, option 3 is the correct answer.}$

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
}