Video Transcript
Fill in the blank. When electrons form chemical bonds,
electrons are promoted and the atom enters blank state. (A) A hybridized, (B) a sigma, (C)
a tetrahedral, (D) an excited, or (E) an overlapped.
In this question, we want to know
which of the answer choices provided in the question describes electron promotion
during bonding. During bonding, hybridization
occurs where atomic orbitals mix into new and different types of hybrid
orbitals. During this process, electrons from
lower energy subshells are promoted to vacant higher energy orbitals. When electrons exist in this
promoted state the atom to which they belong is referred to as being excited or in
an excited state.
For example, carbon — which has an
atomic number of six, thus has six protons, and thus six electrons in a neutral atom
— has this ground or unexcited state. This state is the most stable
arrangement of electrons in a carbon atom.
When there is an input of energy,
one of the two s electrons gains this energy and is promoted to a higher energy
subshell. We say the atom is in the excited
state. The orbitals of the valence shell
can now mix or hybridize. The hybrid orbitals can then
undergo bonding with orbitals from another atom. So for hybridization and bonding to
occur, electrons are first excited or promoted. When electrons form chemical bonds,
electrons are promoted and the atom enters (D), an excited state.
