Ammonia
Ammonia (NH3) is a colorless gas with a characteristic pungent odor. It is a compound of nitrogen and hydrogen and is a common nitrogen waste product of many aquatic organisms. It is also produced in the soil from decaying organic matter.
Chemical Properties:
Ammonia is a basic gas and readily dissolves in water to form ammonium hydroxide (NH4OH), a weak base. It reacts with acids to form ammonium salts. Ammonia is a polar molecule due to the difference in electronegativity between nitrogen and hydrogen. The nitrogen atom has a lone pair of electrons, making ammonia a Lewis base.
Physical Properties:
- Molecular formula: NH3
- Molar mass: 17.031 g/mol
- Melting point: -77.73 °C (-107.91 °F; 195.42 K)
- Boiling point: -33.34 °C (-28.01 °F; 239.81 K)
- Density (liquid): 0.6819 g/cm3 (at -33.3 °C)
- Density (gas): 0.769 kg/m3 (at 0 °C, 1 atm)
- Solubility: Highly soluble in water
Production:
Ammonia is primarily produced industrially through the Haber-Bosch process, which involves the direct combination of nitrogen and hydrogen gases under high pressure and temperature with the aid of a catalyst.
Uses:
Ammonia has a wide range of applications, including:
- Fertilizers: A major component in the production of fertilizers for agriculture.
- Manufacturing: Used in the production of various chemicals, plastics, synthetic fibers (like nylon and rayon), and explosives.
- Cleaning Agents: An ingredient in some household and industrial cleaning solutions.
- Refrigeration: Used as a refrigerant in industrial refrigeration systems.
- Water Treatment: Used to control pH and disinfect water supplies.
- Pharmaceuticals: Used in the production of various pharmaceutical drugs.
Safety:
Ammonia is a corrosive and toxic gas. Inhalation of high concentrations can cause severe irritation to the respiratory system, including burns and pulmonary edema. Direct contact with liquid ammonia can cause frostbite. It is crucial to handle ammonia with appropriate safety precautions, including adequate ventilation and the use of personal protective equipment.
Environmental Impact:
Ammonia emissions from agricultural activities, particularly from livestock and fertilizer use, can contribute to air and water pollution. Excess ammonia in the environment can lead to eutrophication in aquatic ecosystems and contribute to the formation of particulate matter in the atmosphere.