Noble Gases

Where are noble gases located in the periodic table?

• In the first group

• In the central block

• In the last group

• In the second group

Answer explanation

Noble gases are located in the last group of the periodic table, also known as Group 18 or Group 0. They are characterized by their stable and unreactive nature.

Why do noble gases have low chemical reactivity?

• They have incomplete outer shells.

• They have complete outer electron shells.

Answer explanation

Noble gases have low chemical reactivity because they have complete outer electron shells, making them stable and less likely to form bonds.

Which of these could be the electronic structure of a noble gas?

• 2,8,2

• 2,8,8

• 2,8,6

Answer explanation

The correct electronic structure of a noble gas is 2,8,8, indicating a full outer shell with 8 electrons in the outermost energy level.

Which noble gas is used in neon signs?

• Helium

• Neon

• Argon

• Krypton

Answer explanation

Neon is the noble gas used in neon signs, giving them their characteristic bright red-orange glow when electricity passes through it.

Which noble gas has the lowest atomic number?

• Helium

• Neon

• Argon

• Xenon

Answer explanation

Helium has the lowest atomic number among the noble gases, making it the correct choice for this question.

Which noble gas is used in incandescent light bulbs to prevent the filament from reacting with oxygen?

• Neon

• Argon

• Krypton

• Xenon

Answer explanation

Argon is used in incandescent light bulbs to prevent the filament from reacting with oxygen.

What is the main reason noble gases are used in lighting?

• They emit colors when electric current is passed through them.

• They reduce energy consumption.

• They increase the brightness of the light.

• They decrease the production cost.

Answer explanation

The main reason noble gases are used in lighting is that they emit colors when electric current is passed through them.

Which noble gas is not found in significant amounts in the Earth's atmosphere?

• Helium

• Neon

• Argon

• Radon

Answer explanation

Radon is the noble gas not found in significant amounts in the Earth's atmosphere.

What characteristic of noble gases contributes to their lack of colour and odour?

• Their high atomic masses

• Their gaseous state at room temperature

• Their complete outer electron shells

• Their monatomic nature

Answer explanation

The lack of color and odor in noble gases is due to their complete outer electron shells, which makes them stable and less likely to react with other elements.

Which noble gas is primarily used in diving tanks to prevent nitrogen narcosis?

• Helium

• Neon

• Argon

• Krypton

Answer explanation

Helium is primarily used in diving tanks to prevent nitrogen narcosis due to its low solubility in blood, reducing the risk of this condition.