Import Question JSON

Current Question (ID: 8474)

Question:

$\text{At 298 K, the solubility of Sr(OH)}_2 \text{ is 19.23 g/L. The pH of the solution will be:}$

Options:

1. $1.50$
2. $13.50$
3. $0.50$
4. $12.45$

Solution:

$\text{Hint: Use pH} = -\log[\text{H}^+]$ $\text{Step 1: Calculate [OH}^-\text{] using solubility}$ $\text{Solubility of Sr(OH)}_2 = 19.23 \text{ g/L}$ $\text{So, concentration of Sr(OH)}_2 = \left(\frac{19.23}{121.63}\right) \text{ g/L} \div \text{g mol}^{-1} = 0.1581 \text{ M}$ $\text{Sr(OH)}_2\text{(aq)} \rightarrow \text{Sr}^{2+}\text{(aq)} + 2\text{OH}^-\text{(aq)}$ $[\text{OH}^-] = 2 \times 0.1581 \text{ M} = 0.3126 \text{ M}$ $\text{Step 2: Calculate pH using hydroxide ion concentration}$ $K_w = [\text{H}^+][\text{OH}^-]$ $[\text{H}^+] = \frac{10^{-14}}{0.3126} = 3.2 \times 10^{-14} \text{ M}$ $\text{pH} = -\log[\text{H}^+]$ $\Rightarrow -\log(3.2 \times 10^{-14}) = 13.50$

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
}