Import Question JSON

Current Question (ID: 10716)

Question:

$\text{Which of the following statements is false?}$

Options:

1. $\text{He is used in gas-cooled nuclear reactors}$
2. $\text{He is used as a cryogenic agent for carrying out experiments at low temperature}$
3. $\text{He is used to produce and sustain powerful superconducting magnets.}$
4. $\text{He is used to fill gas balloons instead of H}_2 \text{ because it is lighter and non-inflammable.}$ (Correct)

Solution:

{Hint: Helium is heavier than hydrogen, still the element is usually combined with hydrogen in air balloons.}$ $\text{Helium is twice as heavy as hydrogen, its lifting power is 92% of that of hydrogen. Helium has the lowest melting and boiling point of any element which makes liquid helium an ideal coolant for many extremely low-temperature applications such as superconducting magnet and cryogenic research where temperature close to absolute zero is needed.}$ $\text{Since helium is non-inflammable, it is used in filling air-ships and balloons for weather study.}

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
}