Import Question JSON

Current Question (ID: 9170)

Question:

$\text{The cation of alkali metals are found as } \text{M}(\text{H}_2\text{O})_n^+ \text{ in } \text{H}_2\text{O}.$ $\text{The value of 'n' is maximum for -}$

Options:

1. $\text{Na}^+$
2. $\text{K}^+$
3. $\text{Rb}^+$
4. $\text{Li}^+$

Solution:

$\text{HINT: Degree of hydration depends on charge/size ratio.}$ $\text{Explanation:}$ $\text{Metal ions in an aqueous solution behave as Lewis acids. The positive charge on the metal ion draws electron density from the O-H bond in the water.}$ $\text{The extent of hydrolysis of cation depends on the charge on the cation and the size of the cation.}$ $\text{The extent of hydrolysis is directly proportional to the charge on the cation and inversely proportional to the size of the cation.}$ $\text{The charge of the given cations is the same. Thus, the extent of hydrolysis does not depend on the charge.}$ $\text{Here the extent of hydrolysis totally depends on the size of the cation. Down the group size of cation increases and the extent of hydrolysis decreases.}$ $\text{Correct order of degree of hydration: } \text{Li}^+ > \text{Na}^+ > \text{K}^+ > \text{Rb}^+$ $\text{Hence, the correct answer is } \text{Li}^+ \text{ ion.}$

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
}