Redox and Equivalent ConceptHard

Question

29.5 mg of an organic compound containing nitrogen was digested according to Kjeldahl′s method and the evolved ammonia was absorbed in 20 mL of 0.1 M HCl solution. The excess of the acid required 15 mL of 0.1 M NaOH solution for complete neutralization. The percentage of nitrogen in the compound is

Options

A.59.0
B.47.4
C.23.7
D.29.5

Solution

Moles of HCl reacting with
ammonia = (moles of HCl absorbed ) - (moles of NaOH solution required)
          = (20 × 0.1 × 10-3) - (15 × 0.1 × 10-3)
          = moles of NH3 evolved.
          = moles of nitrogen in organic compound]
         ∴ wt. of nitrogen in org. comp = 0.5 × 10-3 × 14
                            = 7 × 10-3 g
                        % wt = = 23.7 %

Create a free account to view solution

View Solution Free
Topic: Redox and Equivalent Concept·Practice all Redox and Equivalent Concept questions

More Redox and Equivalent Concept Questions