Question Video: Determining How Many Electrons Beryllium Has in the Outer Shell after Losing Two Electrons | Nagwa Question Video: Determining How Many Electrons Beryllium Has in the Outer Shell after Losing Two Electrons | Nagwa

# Question Video: Determining How Many Electrons Beryllium Has in the Outer Shell after Losing Two Electrons Science • First Year of Preparatory School

Metals in group 2 commonly lose electrons when forming bonds in chemical reactions. Once beryllium has lost two electrons, how many electrons would be found in the outer shell?

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### Video Transcript

Metals in group two commonly lose electrons when forming bonds in chemical reactions. Once beryllium has lost two electrons, how many electrons would be found in the outer shell?

Beryllium is an element in group two of the periodic table. Atoms of beryllium have four electrons. This diagram shows the electronic configuration of an atom of beryllium. The first two electrons are located in the K shell. The remaining two electrons are in the L shell.

The problem tells us that atoms of beryllium tend to lose two electrons. When atoms lose their electrons, the electrons are lost from the outer electron shell. So atoms of beryllium will lose the two electrons from the L shell, leaving two electrons remaining in the K shell.

This happens because atoms tend to lose, gain, or share electrons to attain a stable electronic configuration. Generally, a configuration is stable if there are two electrons in the K shell and eight electrons in the other shells, like L, M, or N.

After beryllium loses two electrons, there are two electrons left in the K shell and no electrons in the other shells. So this electronic configuration is stable. This question wants to know how many electrons will be found in the outer shell after beryllium loses those two electrons. In this case, the outer shell is the K shell.

There are two electrons in the K shell after beryllium loses two electrons. So two electrons is the correct answer to this question.

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