Which electrons in an atom take the most energy, and what are they called?

What Kind of diagram is used to show how many of these electrons an atom has?

What name is given to the elements with eight outer electrons?

Which element belongs to this group, although it has only two electrons?

How many chemical bonds can a single atom of these elements form hydrogen, carbon, nitrogen?

Valence electrons

The electrons in an atom that take the most energy are the outermost electrons, also known as valence electrons.

To determine the number of valence electrons in an atom, you can refer to the periodic table. For main group elements (those in groups 1, 2, and 13-18), the group number tells you the number of valence electrons. For example, elements in Group 1 have 1 valence electron, elements in Group 2 have 2 valence electrons, and so on.

A diagram commonly used to show the number of valence electrons an atom has is the Lewis electron dot diagram. In this diagram, the symbol of the element represents the atomic nucleus and inner electrons, while dots around the symbol represent valence electrons. Each dot represents one valence electron.

Elements with eight outer electrons are called noble gases. Noble gases are located in Group 18 of the periodic table.

The element that belongs to this group, although it has only two electrons, is helium (He). Helium is unique in that it satisfies the octet rule with just two valence electrons.

The number of chemical bonds a single atom of an element can form depends on the number of valence electrons it has.

Hydrogen (H) has one valence electron and can form one chemical bond.

Carbon (C) has four valence electrons and can form four chemical bonds.

Nitrogen (N) has five valence electrons and can form three chemical bonds.

It's important to note that these are the typical number of bonds formed by these elements, but there can be exceptions depending on the specific molecular arrangement.