Question

In a nonpolar covalent bond,

Answer 1

Answer:

#11: In a nonpolar covalent bond, electrons are shared equally between two atoms.

#12: Only the diatomic nitrogen molecule $\rm N_2$ contains a triple covalent bond among the four molecules.

Explanation:

#11

Consider: what is a covalent bond?

Two atoms share a pair of electrons (called a bonding pair as opposed to a lone pair) between them.

Nonpolar covalent bonds exist only between atoms with similar electronegativity values. The two bonding atoms attract the bonding pair with similar strength, such that the bonding pair is shared mostly equally between the two atoms.

In case the two atoms differ in their electronegativity, the bonding pair will be closer to the more electronegative atom. That will make a polar covalent bond.

#12

Atoms share electrons with each other to achieve an octet of eight valence electrons (two for hydrogen.) Atoms form a covalent bond for every two valence electrons that they need.

Consider: how many electrons do atoms in each molecule need to gain before achieving an octet?

Fluorine is in group 17 of the new IUPAC periodic table. Each fluorine atom needs 18 - 17 = 1 valence electron to achieve an octet. There are two fluorine atoms in an $\rm F_2$ molecule. These two atoms will need two electrons in total to achieve an octet. They will thus need to form $2/2 = 1$ covalent bond.

Similarly:

• Nitrogen is in group 15.
• Each Nitrogen atom is 18 - 15 = 3 electrons away from an octet.
• There are two nitrogen atoms in each $\rm N_2$ molecule.
• The two nitrogen atoms need six more electrons in total and will form $6/2 =3$ covalent bonds.

• Oxygen is in group 16.
• Each oxygen atom is 18 - 16 = 2 electrons away from an octet.
• There are two oxygen atoms in each $\rm O_2$ molecule.
• The two oxygen atoms need four more electrons in total and will form $4/2 =2$ covalent bonds.

• Hydrogen is a special case in the "octet" rule.
• Each hydrogen atom needs one valence electron to attain the electron configuration of the next noble gas element, He.
• There are two hydrogen atoms in each $\rm H_2$ molecule.
• The two hydrogen atoms need two more electrons in total and will form $2/2 =1$ covalent bonds.

Answer 2

Answer:

11.  Electrons are shared equally by two atoms.

12. Diatomic nitrogen

Explanation:

An example of  the  the first  bond is the diatomic hydrogen.

There are 5  electrons in the nitrogen atom's outer shell. The 2 nitrogen atoms will each share 3 electrons to form 3 covalent bonds.