Noble Gases - The Gases In Group 18 | Properties of Matter | Chemistry | FuseSchool

Summary

This lesson explores the fascinating world of noble gases, the group 18 elements including helium, neon, argon, krypton, xenon, and radon. Known for their full valence electron shells, these gases are highly stable, colorless, and monatomic. The video covers their unique properties, such as increasing atomic size, boiling point, and density down the group. It also highlights their diverse applications, from helium in balloons and airships, neon in signs, and xenon in headlights, to medical uses like xenon anesthesia and radon radiotherapy. Industrial uses, such as krypton in double-glazing and xenon as a spacecraft propellant, demonstrate their vital role in everyday life and technology.

Takeaways

• 🎈 Noble gases, such as helium, neon, argon, krypton, xenon, and radon, are all filled in party balloons, neon signs, and some light bulbs.
• 🔬 They belong to group 18 elements and are notable for having full valence electron shells, making them very stable.
• ⚡ Helium has 2 valence electrons, while the other noble gases have 8, which contributes to their chemical inertness.
• 🧪 Though historically called inert gases, some noble gases can form compounds under certain conditions.
• 🌌 All noble gases are colorless, monatomic, and their atomic size increases down the group due to additional electron shells.
• 🌡️ Boiling points and densities increase down the group because larger atoms have stronger intermolecular forces and occupy more space.
• 🎈 Helium is used in balloons and airships because it is less dense than air.
• 💡 Neon emits bright orange light in signs, argon protects tungsten filaments in bulbs, and xenon is used in bright car headlights and lasers.
• 🏥 Xenon serves as a natural anesthetic with minimal side effects, while radon’s radioactivity is applied in radiotherapy.
• 🏢 Krypton improves insulation in double-glazed windows, and xenon is used as a propellant for satellites in space navigation.

Q & A

What common feature do party balloons, neon signs, and certain light bulbs share?

They are all filled with a noble gas.

Which elements are classified as noble gases?

Helium, neon, argon, krypton, xenon, and radon, which are all Group 18 elements.

Why are noble gases considered very stable?

Because they have full valence electron shells, making them largely unreactive under normal conditions.

How many valence electrons do noble gases have?

Helium has 2 valence electrons, while the other noble gases have 8 valence electrons each.

Why do boiling points of noble gases increase down the group?

Because larger atoms with more electrons have stronger intermolecular forces, requiring more energy to boil.

How does the atomic size of noble gases change as you move down the group?

The number of electron shells increases, making the atoms larger as you go down the group.

What are some practical uses of helium?

Helium is used to fill party balloons and airships because it is less dense than air, allowing them to float.

Which noble gases are used in lasers and car headlights?

Krypton and xenon are used in lasers, and xenon is increasingly used in car headlights for bright light and better visibility.

How is argon used in light bulbs?

Argon is used to fill light bulbs because it is inert and does not react with the tungsten filament.

What medical applications do noble gases have?

Xenon acts as a natural anesthetic with few side effects, while radon is used in radiotherapy for cancer treatment.

How is krypton used in construction and insulation?

Krypton is used as a filler between double-glass panels for insulation because it has lower thermal conductivity than air.

What role does xenon play in space technology?

Xenon is used as a propellant to steer satellites in orbit due to its mass, which allows effective movement in space.

Why were noble gases once called inert gases?

Because chemists initially believed they could not react with any other elements due to their stable electron configurations.