Import Question JSON

Current Question (ID: 18857)

Question:

$\text{A diamagnetic lanthanoid ion among the following is:}$ $\text{(At. numbers: Ce = 58, Sm = 62, Eu = 63, Yb = 70)}$

Options:

1. $\text{Ce}^{2+}$
2. $\text{Eu}^{2+}$
3. $\text{Sm}^{2+}$
4. $\text{Yb}^{2+}$

Solution:

$\text{Lanthanoid ion with no unpaired electron is diamagnetic in nature.}$ $1. \text{Electronic configuration: } \text{Ce}_{58} = [\text{Xe}]4f^25d^06s^2$ $\text{Ce}^{2+} = [\text{Xe}]4f^2 \text{ (two unpaired electrons)}$ $2. \text{Electronic configuration: } \text{Sm}_{62} = [\text{Xe}]4f^65d^06s^2$ $\text{Sm}^{2+} = [\text{Xe}]4f^6 \text{ (six unpaired electrons)}$ $3. \text{Electronic configuration: } \text{Eu}_{63} = [\text{Xe}]4f^75d^06s^2$ $\text{Eu}^{2+} = [\text{Xe}]4f^7 \text{ (seven unpaired electrons)}$ $4. \text{Electronic configuration: } \text{Yb}_{70} = [\text{Xe}]4f^{14}5d^06s^2$ $\text{Yb}^{2+} = [\text{Xe}]4f^{14} \text{ (no unpaired electrons)}$ $\text{Because of the absence of unpaired electrons, } \text{Yb}^{2+} \text{ is diamagnetic.}$

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
}