We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What Is Hydrolysis?

By H. Colledge
Updated May 21, 2024
Our promise to you
All The Science is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At All The Science, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Hydrolysis is a type of chemical reaction that occurs between water and another compound. During the reaction, chemical bonds are broken in both molecules, causing them to break apart. The water molecule splits to form positively charged hydrogen (H+) and negatively charged hydroxide (OH-) ions, and the other molecule splits into two simpler sections, also with positive and negative charges. H+ and OH- ions attach to each of these sections. These reactions take place when some ionic compounds, for example, certain acids, bases, and salts, dissolve in water; they are involved in processes that are essential to life; they are used in some important industrial processes, such as the manufacture of soap; and they play an important part in the weathering of rocks.

Ionic Compounds

Ionic compounds can be acids, bases or salts, which are compounds that result from the reaction of an acid and a base. They are made up of positively charged cations and negatively charged anions. When they are dissolved in water, they will split into their cations and anions. The anions of weak acids, and the cations of weak bases, will react with water to some extent, resulting in hydrolysis.

Where a salt is the product of a strong acid and a weak base, the cation of the base will hydrolyze in water. For example, ammonium chloride (NH4Cl) is the salt of a weak base — ammonia (NH3) — and a strong acid — hydrochloric (HCl). When dissolved in water, it splits into cations and anions — NH4+ and Cl-, respectively. The cation, however, will react with water to some extent by losing a hydrogen ion:

NH4+ + H2O <-> NH3 + H3O+

Since this reaction produces hydronium ions (H3O+), the resulting solution is acidic. Where a salt is the product of a strong base and a weak acid, the anions of the acid will react with water by accepting hydrogen (H+) ions, leaving hydroxide (OH-) ions, which gives an alkaline solution. The salt of a strong acid and a strong base will not hydrolyze because the anion of the acid and the cation of the base do not react with water.


Many processes that are essential to life involve hydrolysis. An example is the release of energy by the molecule adenosine triphosphate (ATP). Cells use this compound to store energy, which can then be released when it is needed. The molecule has three phosphate (PO4-) groups, but it can lose one of these groups by reacting with water. This reaction actually uses up a small amount of energy, but much more is released by the subsequent reactions of the free phosphate group.

Hydrolysis is also plays a vital role in the breakdown of food into easily absorbed nutrients. Most of the organic compounds in food do not react readily with water, and usually a catalyst is required to allow these processes to take place. Organic catalysts that help with reactions in living organisms are known as enzymes. In the body, enzymes such as lipases, carbohydrases and proteases catalyze the reactions with fats, carbohydrates and proteins with water.

One example of hydrolysis is the breakdown of starch, which is catalyzed by the enzyme amylase. Starch is broken down into smaller molecules, which consist of the sugar known as maltose. Maltose may then be further broken down into glucose molecules, under the influence of the enzyme maltase. In each case, water takes part in the process, itself splitting and adding a hydroxyl group and a hydrogen ion to the new molecules formed on each side of the broken bond.


Many industrial procedures require various substances to be hydrolyzed to create useful products. Often, however, the raw materials for these processes do not react easily with water molecules, so the reactions are helped by a variety of means, such as high pressure, high temperatures and catalysts. Laboratory hydrolysis usually requires the use of a catalyst, which is typically a strong acid or alkali.

Hydrolysis has been used for a long time in the production of soap. During this process, known as saponification, fat is hydrolyzed in a reaction with water and the strong alkali, sodium hydroxide. The reaction produces fatty acid salts, commonly known as soap. Saponification sometimes occurs in old oil paintings when fatty acids in oil paint react with the metals in paint pigments. This can cause white deposits and lumps to develop on the surface of paintings, although it is not known why it only occurs on some artworks and not others.


Hydrolysis is an important process in the weathering of rocks. Various silicate minerals, such as feldspar, undergo slow hydrolysis reactions with water, forming clay and silt, along with soluble compounds. This process is important in the formation of soils, and in making essential minerals available to plants.

All The Science is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Discussion Comments
By anon320325 — On Feb 17, 2013

Is there a usage of hydrolysis in power generation industry?

By hyrax53 — On Dec 07, 2011

@DentalFloss- I went to a college that had Norwegian ancestry, and they served lutefisk every year. I had forgotten that it used hydrolysis, though. Funny; I wonder if you could use a piece of lutefisk as soap!

By DentalFloss — On Dec 06, 2011

I personally cannot think of hydrolysis and soap without also thinking of fish- specifically, lutefisk. It is a Norwegian dish, mainly eaten these days by Norwegian Americans. This dish is made by soaking dried, salted fish in lye for an extended amount of time. This makes the fish turn into a sort of gelatinous form, and when cooked it is either boiled or pan fried, usually, and then served. The taste is, well, what you might expect fish covered in lye to taste like.

By cardsfan27 — On Dec 05, 2011

Does anyone here have any idea of the industrial processes that use hydrolysis to make their products? I have been trying to think of some, but can't really come up with anything.

Since the article talks about hydrolysis being used to split up starches into glucose, the thing I was kind of thinking about might be in sugar production somehow.

If you had sugar cane or beets or something and needed to separate the sugar from the rest of the plant, you might be able to use hydrolysis to get what you needed.

I was reading something about ethanol the other day, too. Part of the problem with that is that it is hard to separate all of the parts of a plant into things you can and can't use, so I think hydrolysis might have a purpose there, too.

Does anyone else have any ideas?

By jcraig — On Dec 05, 2011

@Izzy78 - I agree. The ways our body gets us nutrients is really spectacular. Besides the things mentioned in the article like breaking down starches, what I was thinking about was how our white blood cells kill bacteria. I don't know it for a fact, but I would be willing to guess that they use some sort of hydrolysis reaction.

I know they have different molecules that they use to break apart, or lyse, bacteria. I assume that they work because the molecules react with the water molecules in the bacteria and cause them to break apart. The interesting thing would be how the white blood cells stop the molecules from tearing them apart.

The other part of the article I like was the weathering of rocks. I knew it was causes by wind and water, but I guess I had never really thought about the actual chemical processes that worked to break down a rock.

By Izzy78 — On Dec 04, 2011

@jmc88 - Good question. I actually just got done watching a TV show that demonstrated how they make soap. They talked about hydrolysis, which led me here.

Basically, lye is the sodium hydroxide that was mentioned in the article. Whenever fat and lye mix, they cause the byproducts to form, and that is what we use to wash our hands. The way it works is because the fat molecules can combine with dirt molecules and then the water washes them all away. Obviously, our soap making to day is much more sophisticated, so we don't have to worry about getting burned by lye.

I didn't realize there were so many different things that used hydrolysis, especially in our bodies. Does anyone know if there are any more good examples?

By jmc88 — On Dec 03, 2011

Wow, I never knew about the process of saponification. In our house, we have a picture that my great, great grandmother painted of the house they used to live in during the 1800s. As long as I can remember, it has had the little white globs that the article mentioned, but we never knew what caused it or whether we should try to get rid of them. I guess it was just science in action! Now that I know what is causing it, I might be able to look into how to restore the picture if it isn't too much of a problem.

On the same topic of saponification and soap making goes, does that mean that we are washing our hands with fat? How does that help to clean them, and what causes the bubbles and suds to form? I know in the past when they made soap, they used lye. What was that?

All The Science, in your inbox

Our latest articles, guides, and more, delivered daily.

All The Science, in your inbox

Our latest articles, guides, and more, delivered daily.