Video Transcript
Which statement correctly describes
covalent bonding? Statement (1) covalent bonding
involves the transfer of electrons. The bonds that are formed are
strong and require a lot of energy to break them. Statement (2) covalent bonding
involves the transfer of electrons. The bonds that are formed are weak
and do not require much energy to break them. Statement (3) covalent bonding
involves the sharing of electrons. The bonds that are formed are
strong and require a lot of energy to break them. Statement (4) covalent bonding
involves the sharing of electrons. The bonds that are formed are weak
and do not require much energy to break them. (A) Statement 1, (B) statement 2,
(C) statement 3, or (D) statement 4.
Let’s start by clearing some
space. Covalent bonding occurs between
nonmetals. For example, a covalent bond forms
between two hydrogen atoms to form diatomic gaseous hydrogen. Each neutral atom of hydrogen has
one electron. When the atoms react, the two
electrons are shared between the two atoms. This means that both atoms have two
electrons in their outer shell, so they both have a full outer shell of
electrons.
The bond in a hydrogen molecule is
a single covalent bond. Double and triple covalent bonds
can also form, such as in oxygen and nitrogen, respectively. In all cases, electrons are
shared. This allows each atom to have a
full outer shell of electrons. Each hydrogen atom has two outer
shell electrons. And each atom in both oxygen and
nitrogen has eight outer shell electrons.
We have determined that covalent
bonding involves the sharing of electrons. In fact, covalent bonds can be
defined as chemical bonds that are formed when two nonmetal atoms share one or more
pairs of electrons. Additionally, although interactions
between covalent molecules are often weak and easy to break, covalent bonds are
strong and difficult to break.
Now that we know how to describe
covalent bonds, let’s bring back the answer choices. We know that covalent bonding
involves the sharing of electrons. Thus, we can eliminate answer
choices (A) and (B), which are statements (1) and (2), respectively, as they state
that covalent bonding involves the transfer of electrons. We also know that covalent bonds
are strong. Since they are strong, a lot of
energy is required to break them. Therefore, statement (3) is
correct, and statement (4) is incorrect.
Thus, the statement which correctly
describes covalent bonding is (C), statement (3). Covalent bonding involves the
sharing of electrons. The bonds that are formed are
strong and require a lot of energy to break them.