Kr

Definition

Kr, or krypton, is a dense, colorless, and odorless noble gas that is one of the six naturally occurring noble gases. It is found in the Earth's atmosphere and has unique properties that make it useful in various applications.

5 Must Know Facts For Your Next Test

1. Krypton has an atomic number of 36 and an atomic mass of 83.798 g/mol, making it the third-heaviest of the noble gases.
2. Krypton is present in the Earth's atmosphere at a concentration of approximately 1 part per million.
3. Krypton is primarily obtained as a by-product during the fractional distillation of liquid air, a process used to separate the components of air.
4. Krypton is used in high-intensity electric discharge lamps, such as those used in photography, and in some types of lasers.
5. Krypton is also used in certain types of insulated glass windows to improve their thermal efficiency.

Review Questions

• Describe the occurrence and preparation of krypton.
  • Krypton is a naturally occurring noble gas that is present in the Earth's atmosphere at a concentration of approximately 1 part per million. It is primarily obtained as a by-product during the fractional distillation of liquid air, a process used to separate the components of air. The fractional distillation process involves cooling and compressing air to the point where the different gases liquefy and can be separated based on their boiling points. Krypton is then further purified and collected for use in various applications.
• Explain the unique properties of krypton that make it useful in various applications.
  • Krypton is a dense, colorless, and odorless noble gas with an atomic number of 36 and an atomic mass of 83.798 g/mol. These properties, along with its low reactivity, make krypton useful in several applications. Krypton is used in high-intensity electric discharge lamps, such as those used in photography, due to its ability to produce intense light when excited by an electric current. Additionally, krypton is used in certain types of insulated glass windows to improve their thermal efficiency, as the gas's low thermal conductivity helps to reduce heat transfer through the glass.
• Analyze the role of krypton in the context of the noble gases and their properties.
  • Krypton is one of the six naturally occurring noble gases, which also include helium, neon, argon, xenon, and radon. As a noble gas, krypton is characterized by its extremely low reactivity and stable electronic configuration, which is a result of its full outer electron shell. This low reactivity is a defining feature of the noble gases and contributes to their unique properties and applications. Krypton's specific atomic number, atomic mass, and abundance in the Earth's atmosphere further differentiate it from the other noble gases, making it a valuable element with its own set of practical uses, such as in lighting and insulation technologies.

Related terms

Noble Gases:

The group of six elements in the periodic table (helium, neon, argon, krypton, xenon, and radon) that are characterized by their extremely low reactivity and stable electronic configurations.

Atomic Number:

The number of protons in the nucleus of an atom, which determines the element's identity and chemical properties.

Atomic Mass:

The total mass of the protons and neutrons in the nucleus of an atom, which determines the element's weight.