In Dumas' method, 292 mg of an organic compound released 50 mL of nitrogen gas () at 300 K temperature and 715 mm Hg pressure. The percentage composition of 'N' in the organic compound is % (Nearest

Question

In Dumas' method, 292 mg of an organic compound released 50 mL of nitrogen gas () at 300 K temperature and 715 mm Hg pressure. The percentage composition of 'N' in the organic compound is  % (Nearest integer)

(Aqueous tension at 300 K = 15 mm Hg)

Canvas Classes · Accepted Answer

Step 1: Correct for Aqueous Tension

The  gas is collected over water at 300 K:

Step 2: Convert Volume to STP

Given:  mL,  K,  mm Hg

STP:  K,  mm Hg

Step 3: Apply Dumas Formula

Mass of compound = 292 mg = 0.292 g

Step 4: Conclusion

%N = 18 (nearest integer)

Key Points to Remember:
- Convert mg to g before substituting in formula ( must be in grams)
- Apply all three correction steps: aqueous tension → STP conversion → Dumas formula
-  (a useful shortcut: )
- Dumas method applies t

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