Urea fertilizer analysis: approximately what percentage of nitrogen does standard agricultural urea contain?

Introduction / Context:
Urea is the most commonly used solid nitrogen fertilizer worldwide due to its high analysis, favorable cost per unit N, and ease of handling. Knowing its nitrogen percentage is essential for calculating application rates and comparing with other N sources like ammonium sulphate or CAN.

Given Data / Assumptions:

• The question asks for the typical N content of standard prilled or granular urea.
• No coated or specialty formulations are implied.
• Mass percentages are rounded to whole numbers for field calculations.

Concept / Approach:
The chemical formula of urea is CO(NH2)2. Its theoretical nitrogen content is approximately 46% by mass, which is widely cited on product labels. This high analysis reduces transportation and application costs per kilogram of nitrogen delivered to the field.

Step-by-Step Solution:
Compute quickly from formula: urea has two nitrogen atoms per molecule.Theoretical composition yields ~46% N by mass.Therefore, choose 46 as the standard fertilizer analysis value.

Verification / Alternative check:
Standard fertilizer handbooks and bag labels report “46-0-0” (N-P2O5-K2O), confirming 46% nitrogen content for conventional urea.

Why Other Options Are Wrong:
10% and 28% are far below urea’s analysis; 80% and 94% are chemically impossible for this compound.

Common Pitfalls:
Confusing urea with ammonium nitrate (≈34% N) or CAN (~25–27% N), or forgetting that coatings (e.g., sulfur-coated urea) slightly reduce the net N percentage but the base product remains 46% N.

Final Answer:
46