Question 1
Classify these bonds as ionic, polar covalent, or nonpolar covalent.
Li-F
Br-Br
F-Br
Question 2
Classify these bonds as ionic, polar covalent, or nonpolar covalent.
K-Cl, H-Br, H-H
Question 3
Answer to question 1
Step 1
Ionic bond refers to the bond which is formed when electrons are transferred between atoms and the bond arises from the coulombic interactions between the oppositely charged species. It involves complete transfer of valence electrons. Example of ionic bond forming compound is NaCl.
On the other hand, covalent bond refers to the bond formed when electron pairs are shared more or less equally between neighboring atoms. When the electron pairs are shared unequally between two atoms , the bond becomes polar because of the electronegative differences, and hence is called polar covalent bond. One example of polar covalent bond is HCl.
Step 2
Li-F is composed of cation Li+ and anion F–, thus the type of bond is ionic.
Br-Br is a diatomic molecule . Diatomic molecule is formed by covalent bonding of same atoms, and , as there is no net dipole moment. Thus, type of bond is covalent non-polar bond.
F-Br also consist of covalent bond and has a net dipole moment towards F. Thus, the type of bond is covalent polar bond.
Answer to question 2
K-Cl -ionic
H-Br -polar covalent
H – H – non polar covalent.
Explanation is given below
There are three types of bonds:
1. Nonpolar covalent: equal sharing of electrons between 2 atoms in a bond I.e., the electronegativity value of both the bonded atoms are nearly equal.
2. Polar covalent: uneven sharing. Electrons in the bond hang out with the more electronegative element. I.e., the electronegativity difference between the two bonded atoms is not very high.
3. Ionic: The more electronegative atom is so strong, it steals the electron. I.e., the electronegativity difference between the bonded atoms is very high.
In K-Cl the electronegativity value of K is 0.8 and 3.0 of Cl and the difference is 2.2 that means the the compound is ionic. Therefore KCl is ionic compound.
In H-Br the electronegativity value of H is 2.1 and 2.8 of Br and the electronegativity difference is 0.7 which is not high to make the compound ionic but it can be polar. Therefore the molecule HBr is polar covalent
in H-H, both the H atom have the same value of electronegativity that means the difference is zero. Since electronegativity difference is 0 therefore the molecule is neither ionic nor polar. H-H is non polar covalent.
Answer to question 3
Step 1
A covalent bond is formed by sharing of electrons while an ionic bond is formed by complete transfer of electrons.
covalent bond may be polar or non-polar.It depends on the electronegativity value of bonded atoms.
Step 2
