The Elements: Helium

The video explains nuclear fusion, which forms helium atoms and generates heat and light. Helium is abundant in the universe but rare on Earth due to its lightness, causing it to escape into space. It has the lowest melting and boiling points, making it useful as a coolant in nuclear reactors and MRI scans. Helium is also used to pressurize rocket fuel tanks and in scuba diving mixtures to withstand high pressures.

What process is responsible for the formation of helium atoms?

• Radioactive decay

• Chemical reaction

• Nuclear fusion

• Nuclear fission

Why is helium rare on Earth despite being abundant in the universe?

• It reacts with other elements to form compounds.

• It is incredibly light and escapes into space.

• It is too heavy to remain in the atmosphere.

• It is absorbed by the Earth's core.

What property of helium allows balloons filled with it to rise?

• Low density

• High melting point

• High density

• Low reactivity

In which of the following applications is liquid helium used due to its low temperature?

• As a fuel in rockets

• In the manufacturing of glass

• As a coolant in MRI scans

• In the production of steel

What is the purpose of using a mixture of oxygen and helium, known as helios, in scuba diving?

• To increase buoyancy

• To reduce the risk of decompression sickness

• To enhance breathing efficiency

• To improve underwater visibility