1. What is Percentage Yield of Nitrogen using Kjeldahl's Method?

Definition: This calculator estimates the percentage yield of nitrogen in an organic compound using Kjeldahl's method, which involves acid digestion and titration.

Purpose: It helps chemists and researchers determine the nitrogen content in organic samples, important for protein analysis and quality control.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( N\% \) — Percentage yield of nitrogen
• \( N_{acid} \) — Normality of the acid used (N)
• \( V_{acid} \) — Volume of acid used (mL)
• \( M \) — Mass of the compound (g)

Explanation: The formula calculates the nitrogen percentage based on the amount of acid required to neutralize the ammonia produced during digestion.

3. Importance of Nitrogen Percentage Calculation

Details: Accurate nitrogen determination is crucial for protein estimation, fertilizer analysis, and quality control in food and agricultural products.

4. Using the Calculator

Tips: Enter the normality of the acid used, volume of acid consumed in titration (in mL), and mass of the compound (in grams). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the constant 1.4 in the formula?
A: The factor 1.4 accounts for the conversion between milliequivalents of acid to percentage nitrogen (14 mg nitrogen per meq).

Q2: What acids are typically used in Kjeldahl's method?
A: Sulfuric acid is commonly used for digestion, while hydrochloric acid or sulfuric acid is used for titration.

Q3: What sample size is recommended?
A: Typically 0.2-2.0 grams of sample is used, depending on expected nitrogen content.

Q4: Can this method measure all nitrogen forms?
A: No, Kjeldahl's method measures only nitrogen in amino, amide, and ammonium forms, not nitro or azo compounds.

Q5: How accurate is this method?
A: With proper technique, results are typically within ±1% of the true value for most organic compounds.