Import Question JSON

Current Question (ID: 7649)

Question:

$\text{The correctly matched option is:}$

Options:

1. $\text{Fe}^{3+} > \text{Fe}^{2+} > \text{Fe}^+ \text{ : Order of atomic radius}$
2. $\text{O} > \text{C} > \text{B} > \text{N} \text{ : Order of ionisation energy}$
3. $\text{O}^{2-} < \text{O}^- < \text{O} < \text{O}^+ \text{ : Increasing order of } Z_{\text{eff}}$ (Correct)
4. $\text{O} < \text{N} < \text{F} < \text{Ne} \text{ : Order of electron affinity}$

Solution:

$\text{HINT: Electron affinity and } Z_{\text{eff}} \text{ increases left to right.}$ $\text{Explanation:}$ $\text{For cation, if the positive charge on cation increases then its radius decreases because effective nuclear charge increases. So, } \text{Fe}^{3+} > \text{Fe}^{2+} > \text{Fe}^+ \text{ is wrong.}$ $\text{From left to right, Ionisation energy generally increases and nitrogen has higher ionization energy than oxygen because it has a half-filled 2p orbital. Thus given order, that is O} > \text{C} > \text{B} > \text{N} \text{ is wrong.}$ $\text{Left to right electron affinity increases and halogen have lowest electron affinity but in given sequence, that is,}$ $\text{O} < \text{N} < \text{F} < \text{Ne} \text{ Ne has the highest electron affinity which is not possible. Hence given sequence is wrong.}$ $\text{As the positive charge on the cation increases the } Z_{\text{eff}} \text{ is also increases because in the cation number of protons is more than the number of electrons.}$ $\text{When a number of protons are more than a number of electrons then } Z_{\text{eff}} \text{ is more.}$ $\text{Hence, the } \text{O}^{2-} < \text{O}^- < \text{O} < \text{O}^+ \text{ order is correct.}$

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
}