Import Question JSON

Current Question (ID: 8781)

Question:

$\text{The mass of a box measured by the grocer's balance is 2.300 kg. Two gold pieces of masses 20.15 g and 20.17 g are added to the box. The total mass of the box and the difference in the masses of the gold piece should be recorded to correct significant figures will be respectively:}$

Options:

1. $\text{2340.32 g, 0.002 g}$
2. $\text{2.340 kg, 0.02 g}$
3. $\text{2.3 kg, 0 g}$
4. $\text{2.334032 kg, 0.02 g}$

Solution:

$\text{Hint: For addition/subtraction, final answer should have least number of significant figures among the given values.}$ $\text{Step 1: Calculate total mass}$ $\text{Convert gold piece masses to kg: 20.15 g = 0.02015 kg and 20.17 g = 0.020217 kg}$ $\text{Total mass = 2.300 kg + 0.02015 kg + 0.020217 kg = 2.340367 kg}$ $\text{For addition/subtraction, the result should have the same number of decimal places as the measurement with the fewest decimal places. Since 2.300 kg has 3 decimal places, the answer should be rounded to 2.340 kg.}$ $\text{Step 2: Calculate difference in gold piece masses}$ $\text{Difference = 20.17 g - 20.15 g = 0.02 g}$ $\text{Both measurements have 2 decimal places, so the result is 0.02 g.}$ $\text{Therefore, the correct answer is 2.340 kg, 0.02 g.}$

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
}