The key difference between covalent bond and dative bond is that the covalent bond forms when unpaired electrons of two atoms associate with each other whereas the dative bond forms when an atom donates one of its electron pairs to another atom.
Although the dative bond looks like a covalent bond, they are different from each other when we consider the formation of the bond. But, there is no difference between covalent bond and dative bond after its formation. Therefore, we usually call the dative bond a covalent bond, which is not wrong.
CONTENTS
1. Overview and Key Difference
2. What is Covalent Bond
3. What is Dative Bond
4. Side by Side Comparison – Covalent Bond vs Dative Bond in Tabular Form
5. Summary
What is Covalent Bond?
A covalent bond is a form of chemical bond that forms when two atoms share an electron pair. We call it a “molecular bond”. The electrons that are being shared are “shared pairs” or “bonding pairs”. A covalent bond formed due to the stable balance of attractive and repulsive forces between atoms when they share electrons. This electron sharing allows each atom to have the equivalent of a full outer shell. This type of bond forms between two nonmetal atoms having nearly similar electronegativity values or between an electron and a positively charged metal ion.
Figure 01: Formation of a Covalent Bond Between two Hydrogen Atoms
Covalent bonds are mainly of two types; they are polar bonds and nonpolar bonds. Polar bonds exist between two atoms with a difference between their electronegativity values in the range of 0.4 to 1.7. A nonpolar bond forms if this difference is lower than 0.4. This is because, a high difference between electronegativity values means, one atom (having the higher electronegativity value) attracts the electrons more than the other atom does making the bond, polar.
There are three major types of covalent bonds according to the number of electron pairs that are being shared between two atoms. They are single bonds that involve one electron pair, double bonds that involve two electron pairs, and a triple bond that involves three electron pairs.
What is Dative Bond?
A dative bond is a type of covalent bond that forms when one atom donates its electron pair to another atom. After the formation of the bond, it looks exactly like a covalent bond. This is because both atoms share the same electron pair as the bond pair.
Figure 02: Formation of a Dative Bond
Synonyms for this bond are “dipolar bond” and “coordinate bond”. The most common example is the bonds in coordination complexes. There, the metal ions bind with ligands via these coordinate bonds.
What is the Difference Between Covalent Bond and Dative Bond?
A covalent bond is a form of chemical bond that forms when two atoms share an electron pair. A dative bond is a type of covalent bond that forms when one atom donates its electron pair to another atom. They differ from each other according to the way they form. Therefore, the key difference between covalent bond and dative bond is that a covalent bond forms when unpaired electrons of two atoms associate with each other whereas dative bond form when an atom donates one of its electron pairs to another atom.
The below infographic presents the difference between covalent bond and dative bond in tabular form.
Summary – Covalent Bond vs Dative Bond
After the formation of the bond, both covalent bond and dative bond seems similar. However, they differ from each other according to the way that they form. The difference between covalent bond and dative bond is that a covalent bond forms when unpaired electrons of two atoms associate with each other whereas dative bond form when an atom donates one of its electron pairs to another atom.
Reference:
1. Helmenstine, Anne Marie, Ph.D. “Covalent Bond Definition.” ThoughtCo, Jun. 22, 2018. Available here
2. Helmenstine, Anne Marie, Ph.D. “Dative Bond Definition (Coordinate Bond).” ThoughtCo, Jun. 22, 2018. Available here
Image Courtesy:
1.”Covalent bond hydrogen”By Jacek FH – Own work, (CC BY-SA 3.0) via Commons Wikimedia
2.”NH3-BF3-adduct-bond-lengthening-2D”By Ben Mills – Own work, (Public Domain) via Commons Wikimedia