Helium Electron Configuration and Properties

The video explains why helium, despite being in group 18 with noble gases, does not have an octet. It covers the trend of valence electrons across groups, highlighting that helium has only two electrons, filling its highest energy level but not forming an octet. The video also discusses the periodic table's orbital blocks and helium's electron configuration, emphasizing that helium's first energy level is full, which is sometimes referred to as a duet.

Why doesn't helium form an octet?

• It is a noble gas and doesn't react.

• It is located in group 17.

• It has too many electrons.

• It has a full d orbital.

What is the trend for valence electrons in group 18 elements?

• They all have one valence electron.

• They have a full octet, except for helium.

• They have no valence electrons.

• They have six valence electrons.

How many electrons does helium have in its highest energy level?

• Three

• Two

• Four

• One

What is the electron configuration of helium?

• 2p6

• 1s1

• 1s2

• 2s1

What happens if you add another electron to helium?

• It becomes unstable.

• It remains in the same energy level.

• It moves to a new energy level.

• It forms a new element.

Which orbital block does helium belong to?

• F block

• S block

• D block

• P block

What is the atomic number of helium?

• 1

• 4

• 2

• 3

What is the term used to describe helium's full outer shell?

• Octet

• Duet

• Triplet

• Quartet

Why is helium considered inert?

• It has a full outer shell.

• It has an incomplete octet.

• It reacts with most elements.

• It has a high atomic number.

What is the significance of helium's electron configuration?

• It allows helium to form compounds easily.

• It causes helium to have a high melting point.

• It gives helium a stable, inert nature.

• It makes helium highly reactive.