Difference Between Hydrolysis and Hydration

The main difference between hydrolysis and hydration is that hydrolysis involves the splitting of water molecules whereas hydration usually does not always involve splitting of water molecules…

Hydrolysis versus hydration

Hydrolysis is considered as the double decomposition reaction process with water usually as one of the reactants while hydration is considered as the chemical method involving water molecules combining with a substance. Hydrolysis usually occurs with bond breaking in water molecules, while in organic molecules, hydration usually occurs with bond breaking, but bond breaking sometimes does not occur in inorganic compounds.

Hydrolysis produces saturated compounds generally from unsaturated compounds; on the other hand, hydrated compounds are produced by hydration from dehydrated compounds. In hydrolysis, the reaction of an anion, a cation, or sometimes both occurs with water to alter the pH of the water; on the contrary, in hydration, solute molecules are surrounded by solvent molecules. Hydrolysis is considered as the chemical process because it involves the breaking of bonds and molecules; on the other hand, hydration is considered as the physical process because it does not involve any chemical breaking of molecules or bonds.

The pH of hydrolysis increases or decreases during the chemical reaction process in which the anions or cations relatively alter the pH of the water; on the other hand, the hydration pH remains constant in the reaction process. The hydrolysis example is given as Na ₂ CO ₃ + 2H ₂ O → 2NaOH + H ₂ CO _3, while the hydration example is given as K ⁺ Cl ^– + H ₂ O → K ⁺ (aq) + Cl ^– ( aq ).

Comparison chart

What is hydrolysis?

Hydrolysis is the term that generally involves the double decomposition reaction process with water usually as one of the reactants. Hydrolysis is the process of reactions that are frequently reversible.

According to the Bronsted-Lowry acid-base theory in which water can act as either a base or an acid. This theory is stated as: “acid generally produces its conjugate base, and base normally produces its conjugate acid through proton exchange when an acid and a base react with each other.”

If a water molecule functions as a Bronsted-Lowry acid, it means that the water molecules donate a proton. If a water molecule functions as a Bronsted-Lowry base, then it generally means that the water molecule accepts a proton by normally producing the hydronium ion (H ₃ O ⁺ ). H ₂ O ions, H ⁺ ions and OH- ions react with anions and cations to form the base and acid of a salt respectively to give the original base, and the original acid is generally known as hydrolysis.

Hydrolysis considers the chemical process because it involves the breaking of bonds and molecules. The pH of hydrolysis increases or decreases during the chemical reaction process in which anions or cations relatively alter the pH of the water. The main types of hydrolysis, which are acid hydrolysis, basic hydrolysis, and sat hydrolysis.

The example of hydrolysis is given as Na ₂ CO ₃ + 2H ₂ O → 2NaOH + H ₂ CO _3, which describes that when sodium carbonate reacts with water molecules, it usually forms sodium hydroxide (base) and a carbonic acid with the breakdown of water molecules.

Types of hydrolysis

• Acid Hydrolysis: The resemblance to an acid dissociation reaction is generally known as acid hydrolysis.
• Base hydrolysis – The resemblance to a base dissociation reaction is generally known as base hydrolysis. In this hydrolysis, water usually donates a proton forming a hydroxide ion (OH ^– ). Therefore, it means that water generally acts as a Bronsted-Lowry acid.
• Salt hydrolysis: Salt usually separates into its ions when salt is mixed with water. When the salt of a weak acid or a weak base is usually mixed with water, then the water ionizes this salt by mixing and then producing hydronium cations and hydroxide anions. The dissolved salt can also be separated into its anions or cations, which is generally called salt hydrolysis.

What is hydration?

The term hydration is defined as the chemical method, which involves water molecules combining or bonding with a substance. Also, the addition of H ₂ O molecules to ions or substances to produce hydrated salts or hydrated ions is known as hydration. Hydration is considered as the physical process because it does not involve any chemical breaking of molecules or bonds and it is usually formed from desiccants (a compound that can easily absorb water).

The hydration pH remains constant in the reaction process. Hydration of organic molecules usually occurs with bond breaking, but bond breaking sometimes does not occur in inorganic compounds because it is the connotation of water molecules with compounds. In organic chemistry, the water molecules are entering to the point where an unsaturation is available. At this point, the water molecules break down into a hydroxide ion and a proton.

The hydroxide ion generally bonds to a carbon atom, which has more substituents. The proton usually combines with the carbon that has fewer substituents, which generally controls Markovnikov’s rule.

Hydration in inorganic chemistry generally denotes the connectivity of water molecules with an inorganic compound. For example, in the sulphate process, which produces the TiO ₂ pigments usually from ilmenite sand (FeTiO ₃ ), and the by-product that is formed is FeSO ₄ .

When a salt mixes with water, it generally forms the anion and cations, which then separate from each other by hydration of ions through water molecules. In this process, the water molecules often surround the salt ions, which is known as hydration. Hydration example is given as K ⁺ Cl ^– + H ₂ O → K ⁺ (aq) + Cl ^– (aq).

Key differences

1. H ₂ O ions, H ⁺ ions and OH- ions react with anions and cations to form base and acid which is known as hydrolysis; On the other hand, the addition of H ₂ O molecules to ions or substances to produce hydrated salts or hydrated ions is known as hydration.
2. Hydrolysis deliberates as the double decomposition reaction method with usually water as one of the reactants, while hydration deliberates on the chemical method, which involves water molecules associating with a substance.
3. With bond breaking in water molecules, hydrolysis usually occurs, while hydration usually occurs in organic molecules with bond breaking, but many times in inorganic compounds, bond decomposition does not occur.
4. From unsaturated compounds, hydrolysis usually forms the saturated compounds; on the other hand, from dehydrated compounds, hydrated compounds are formed by hydration.
5. The reaction of anion, cation, or sometimes both occur in hydrolysis with water to change the pH of water; on the contrary, in hydration, the binding of solute molecules by solvent molecules occurs.
6. As hydrolysis involves the breaking of bonds and molecules, hydrolysis deliberates as far as the chemical process; on the other hand, since hydration does not involve the chemical breakdown of molecules or bonds, hydration deliberates as to the physical method.
7. The pH of hydrolysis increases or decreases throughout the chemical reaction method; on the other hand, the hydration pH rests constantly in the reaction process.
8. The hydrolysis example is considered as Na ₂ CO ₃ + 2H ₂ O → 2NaOH + H ₂ CO _3, while the hydration example is considered as K ⁺ Cl ^– + H ₂ O → K ⁺ (aq) + Cl ^– ( aq ).

Final Thought

The above discussion concludes that hydrolysis involves the splitting of water molecules, and the pH of hydrolysis increases or decreases during the chemical reaction process in which anions or cations relatively alter the pH of water. While hydration generally does not always involve the splitting of water molecules, and the pH of hydration remains constant throughout the reaction process.