Hydrolysis facts for kids

Hydrolysis is a cool chemical reaction where a chemical compound mixes with water. Think of it like water helping to break things apart! This reaction is often used to split big molecules called polymers into smaller pieces. In hydrolysis, water always joins the chemical compound.

How Water Breaks Down Metal Salts

When certain metal salts mix with water, they can undergo hydrolysis. This process is sometimes called hydration. Many metal ions, which are atoms with an electrical charge, act like strong "acid-lovers" in water. They can react with water to form new types of salts called basic salts.

Why Metal Ions React with Water

Metal ions have a positive charge. This charge strongly attracts water molecules. Water molecules have a special part, an oxygen atom, with extra electrons. When water gets close to a metal ion, the metal ion pulls on these electrons. This pulling changes how the water molecule is put together.

Making Solutions Acidic

When the metal ion pulls on the water molecule, it makes one of the bonds in water (the O-H bond) weaker. This allows the water molecule to release a hydrogen atom as a H+ ion. When H+ ions are released into the water, the solution becomes more acidic.

For example, if you put aluminium chloride into water, it goes through a lot of hydrolysis. This makes the water solution very acidic. When these solutions dry up, they don't leave behind just aluminium chloride. Instead, they leave a basic salt, like an oxychloride.

Common Metal Hydrolysis Examples

You can see this type of reaction with other metal chlorides too. These include ZnCl₂, SnCl₂, FeCl₃, and some rare earth element compounds like DyCl₃.

Sometimes, the hydrolysis reaction goes all the way. For example, with TiCl₄, the reaction with water can completely form a pure hydroxide or oxide. In this case, it forms TiO₂.

Images for kids

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  This picture shows a general hydrolysis reaction. The two-way arrow means the reaction can go both ways.

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  This diagram shows how an acid helps break down a molecule called an amide using hydrolysis.

See also

In Spanish: Hidrólisis para niños