Import Question JSON

Current Question (ID: 21544)

Question:

$\text{The correct order of the following elements with respect to their density is:}$

Options:

1. $\text{Cr} < \text{Zn} < \text{Co} < \text{Cu} < \text{Fe}$
2. $\text{Zn} < \text{Cu} < \text{Co} < \text{Fe} < \text{Cr}$
3. $\text{Zn} < \text{Cr} < \text{Fe} < \text{Co} < \text{Cu}$
4. $\text{Cr} < \text{Fe} < \text{Co} < \text{Cu} < \text{Zn}$

Solution:

$\text{The atomic volumes of the transition elements are low compared to elements in Groups 1 and 2.}$ $\text{This is because the increased nuclear charge is poorly screened and so attracts all the electrons more strongly.}$ $\text{In addition, the extra electrons added occupy inner orbitals.}$ $\text{Consequently, the densities of the transition metals are high.}$ $\text{In the third period, generally, transition element density increases from left to right.}$ $\text{But Zn density is least among all the 3d series elements.}$ $\text{The values are as follows:}$ $\text{Zn} < \text{Cr} < \text{Fe} < \text{Co} < \text{Cu}$ $\text{Density/g cm}^{-3}$ $7.1 \quad 7.19 \quad 7.8 \quad 8.7 \quad 8.9$

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
}