Safety and handling of ammonium nitrate:\nWhich statement is correct regarding fertilizer-grade ammonium nitrate and common practice before field use?

Introduction / Context:
Ammonium nitrate (AN) is a valuable nitrogen source but presents handling and safety challenges. Many markets mitigate its explosive potential and caking tendency by producing calcium ammonium nitrate (CAN), a mixture of AN with ground limestone or dolomite. Understanding these properties is crucial for safe storage and regulatory compliance.

Given Data / Assumptions:

• Fertilizer-grade AN has approximately 34–35% nitrogen, not “N2”.
• AN is hygroscopic, tending to absorb moisture and cake.
• AN can undergo explosive decomposition under certain conditions.

Concept / Approach:
To reduce the explosive hazard and improve physical properties, AN is often diluted with limestone/dolomite to form CAN. The inert solid diluent stabilizes the product, lowers nitrogen concentration, and reduces sensitivity. Statements denying hygroscopicity or explosive risk are incorrect and potentially dangerous. The accurate description highlights the limestone blending practice.

Step-by-Step Solution:
Note AN properties: hygroscopic and potentially hazardous.Identify mitigation: blend with limestone (or dolomite) → CAN.Pick the statement that matches industry practice and safety rationale.

Verification / Alternative check:
Fertilizer safety standards and technical sheets describe CAN as stabilized AN with reduced detonation potential and better storage behavior compared with straight AN.

Why Other Options Are Wrong:
“About 40% N2” misstates both value and unit; AN is hygroscopic; and it is indeed prone to explosive decomposition under misuse; blending with potash is not a universal anti-caking measure for AN.

Common Pitfalls:
Confusing nitrogen percentage with dioxygen/nitrogen gas notation; underestimating storage risks associated with AN.

Final Answer:
It is mixed with limestone powder to reduce explosive hazard before using as fertilizer (CAN)