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NEET CHEMISTRYSome Basic Concepts of ChemistryEasy

Question

The percentages of C, H, and N in an organic compound are 40%, 13.3%, and 46.7% respectively. The empirical formula of the compound is:

A

C₃H₁₃N₃

B

CH₂N

C

CH₄N

D

CH₆N

Step-by-Step Solution

  1. Determine the number of moles of each element: Assume a 100 g100\text{ g} sample of the compound to directly convert percentages to mass.
  • Moles of Carbon (C): 40 g12 g/mol=3.33 mol\frac{40\text{ g}}{12\text{ g/mol}} = 3.33\text{ mol}
  • Moles of Hydrogen (H): 13.3 g1 g/mol=13.3 mol\frac{13.3\text{ g}}{1\text{ g/mol}} = 13.3\text{ mol}
  • Moles of Nitrogen (N): 46.7 g14 g/mol3.335 mol\frac{46.7\text{ g}}{14\text{ g/mol}} \approx 3.335\text{ mol}
  1. Determine the simplest molar ratio: Divide the mole values by the smallest number of moles calculated (3.33 mol3.33\text{ mol}).
  • Ratio for C: 3.333.33=1\frac{3.33}{3.33} = 1
  • Ratio for H: 13.33.334\frac{13.3}{3.33} \approx 4
  • Ratio for N: 3.3353.331\frac{3.335}{3.33} \approx 1
  1. Construct the Formula: The simplest whole number ratio of C:H:N is 1:4:11:4:1. Therefore, the empirical formula is CH4N\text{CH}_4\text{N}.

Exam Context & Concepts Covered

This question aligns with the NEET CHEMISTRY syllabus, specifically targeting concepts from Some Basic Concepts of Chemistry. Mastering this topic is crucial for scoring well in the upcoming medical entrance examinations. Solving conceptually related problems will help you understand the nuances of these concepts and improve your problem-solving speed.

CHEMISTRYSome Basic Concepts of Chemistrypercentagesorganiccompoundrespectivelyempirical

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