Question

Define valence shell and valence electron.

Short answer

Question: Define valence shell and valence electron and provide an example of each concept. Answer: The valence shell is the outermost electron shell of an atom and contains the electrons most likely to be involved in chemical bonding. Valence electrons are the electrons present in this outermost shell and determine an atom's chemical behavior and bonding potential. For example, oxygen has a valence shell with six valence electrons and seeks to complete its shell with eight electrons, making it likely to form chemical bonds with other atoms.

Step-by-step solution

Definition of Valence Shell

The valence shell is the outermost electron shell of an atom. These shells contain the electrons that are most likely to be involved in chemical bonding with other atoms. For an atom to be chemically stable, its valence shell needs to have a full set of electrons. Main-group elements, for example, follow the octet rule, meaning they seek to have eight electrons in their valence shell.

Definition of Valence Electron

Valence electrons are the electrons present in the outermost electron shell (valence shell) of an atom. These electrons typically determine an atom's chemical behavior and are responsible for the formation of chemical bonds between atoms. The number of valence electrons in an atom can be determined using the periodic table by looking at the group number of the element, as elements within the same group have the same number of valence electrons.

Example of Valence Shell and Valence Electron

Let's take a look at a simple example, the element oxygen. Oxygen is in group 16 (or group VI) of the periodic table, which means it has 6 valence electrons. These electrons are located in its valence shell, which is the second energy level (shell) in this case. Oxygen seeks to complete its valence shell with eight electrons, which makes it likely to form chemical bonds with other atoms by either sharing or gaining two more electrons.