Question

The type of bond formed during the hydration of cation is (1) ionic (2) covalent (3) electrostatic (4) dative bond

Short answer

Electrostatic

Step-by-step solution

Understanding the Concept of Hydration of Cations

In hydration of cations, water molecules surround a cation. The slightly negative oxygen atoms of water are attracted to the positive cation. This interaction is due to the electrostatic forces of attraction.

Analyzing the Types of Bonds in Context

Consider the characteristics of the given bond types: Ionic bonds are formed between oppositely charged ions. Covalent bonds involve sharing of electrons between atoms. Electrostatic forces are attractions between opposite charges, but not involving electron sharing. Dative bonds (or coordinate bonds) occur when both electrons in the bond come from the same atom.

Determining the Correct Bond Type

In hydration, the attraction between the cation and the water molecule is purely based on the charge interaction between the positively charged cation and the partially negative oxygen atom. No electron sharing or donation is involved.

Conclusion

The bond formed during hydration of a cation is based on the electrostatic attraction between the cation and the water molecule.

Key concepts

Electrostatic Attraction

Electrostatic attraction is a key concept in understanding various types of chemical interactions. It occurs when opposite electric charges attract one another.
In the context of hydration of cations, electrostatic attraction plays a crucial role. When a cation (positively charged ion) is placed into water, the slightly negative oxygen ends of water molecules are attracted to the cation.
This attraction does not involve sharing or transferring electrons, but rather is purely based on the interaction between the positive charge on the cation and the negative dipole of the water molecule.
This type of force is fundamental to many processes in chemistry, making it important to understand.
For example, electrostatic attraction is responsible for the formation of ionic bonds as well as the interactions seen in polar molecules like water.

Ionic Bonds

Ionic bonds are formed between two oppositely charged ions. This typically occurs when one atom donates an electron to another.
For instance, sodium (Na) can donate an electron to chlorine (Cl), resulting in positively charged sodium ions (Na⁺) and negatively charged chloride ions (Cl^-). These oppositely charged ions then attract each other due to electrostatic forces, forming an ionic bond.
Ionic compounds, like table salt (NaCl), are composed of large numbers of these positive and negative ions held together in a lattice structure through strong ionic bonds.
However, in the hydration of cations, the bonds formed are not ionic because there is no electron transfer happening. Instead, the attraction is purely electrostatic between the cation and the water molecule.
It’s essential to distinguish between these interactions to fully grasp why certain types of bonds form in specific situations.

Dative Bonds

Dative bonds, also known as coordinate covalent bonds, are a type of covalent bond where both electrons in the shared pair come from the same atom.
This is different from a regular covalent bond where each atom supplies one of the electrons in the bond.
A common example of a dative bond occurs in the formation of the ammonium ion (NH₄⁺), where the nitrogen atom donates a pair of electrons to bond with a proton (H⁺).
In hydration of cations, dative bonds are not formed since there is no sharing of electrons from a single atom. Instead, the interaction is based entirely on electrostatic attraction between charged particles.
Understanding dative bonds helps clarify why these are not the type of bonds seen in the interaction between water molecules and cations during hydration.
Recognizing the unique features of dative bonds can also aid in understanding complex bonding scenarios in various chemical compounds.