What is meant by a 'dative' bond?

A 'dative' bond, also known as a 'coordinate' bond, is a type of covalent bond where both electrons come from the same atom.

In more detail, a dative bond is a special type of covalent bond that forms when one atom provides both of the electrons and the other atom does not provide any. This usually happens when an atom with a lone pair of electrons donates them to an atom with an empty orbital, creating a bond. The atom that donates the electrons is known as the 'donor' and the atom that accepts the electrons is known as the 'acceptor'.

This type of bond is different from a regular covalent bond, where each atom provides one electron. However, once the dative bond has formed, it behaves just like any other covalent bond. It's important to note that the direction of the arrow in diagrams represents the movement of the electron pair from the donor atom to the acceptor atom.

Dative bonds are common in many types of compounds, including coordination compounds, where a central metal atom is surrounded by a number of ligands that donate electron pairs. They also play a key role in the formation of complex ions and in certain reactions, such as Lewis acid-base reactions.

Understanding dative bonds is crucial for understanding many aspects of chemistry, including molecular structure, reactivity, and the properties of materials. It's also a key concept in many advanced topics, such as organometallic chemistry and biochemistry. So, while it might seem like a small detail, it's actually a fundamental part of how atoms interact with each other.