The Elements: Nitrogen

Nitrogen is vital for life, found in amino acids, proteins, and DNA. It is crucial for plant photosynthesis and is used in fertilizers. Nitrogen compounds are also used in rocket fuels and explosives. Despite its unreactive nature, nitrogen gas is useful as a food preservative. Liquid nitrogen's cryogenic properties allow scientists to study substances at low temperatures.

Why is nitrogen gas considered unreactive, and how is this property utilized?

What is cryogenic freezing, and how is liquid nitrogen involved in this process?