Caustic Soda, Lye and Sodium Hydroxide – An Overview

Want to use caustic soda, Lye, or sodium hydroxide? But you don't even know where to start? What about all the different names? Yes, we know it can be a little overwhelming but we are here to help break it easier for you. Caustic soda is sodium hydroxide which is lye – they are exactly the same; Just a different name.

The reason behind the different names is mainly to do with the chemical name being “sodium hydrate” and the chemical itself is “caustic or corrosive”, leading to being known as caustic soda. When it comes to the term “lye” it is a common name that relates to sodium hydroxide in the solution to make soap. You can buy sodium hydroxide via to make soap and various other uses.

The nature of caustic soda is usually of a white powder consistency that is either in the form of flake, crystals or pearls, our caustic soda is normally pearls. The different types of forms do not change the outcome of what you are trying to do. Caustic soda can be used in a variety of applications such as soap making, frosting glass, unblocking drains, candle making, and chemical experiments

The reason caustic soda is very good for unblocking and making soap is especially that caustic reacts with fat. This means that it changes the composition that allows it to dissolve fat (in the sink formula or soap) to make soap consistent and this process is called saponification.

It is important to understand the reaction of caustic soda with water. Caustic soda is an exotherm, which means that they produce heat and remove hydrogen. When you add hot water to caustic soda, this process can be very dangerous because it can cause an alkaline explosion where acid can be distributed in all places.

On the contrary, use cold water, even though the process may take longer, it is much safer because caustic soda is exothermic which means hot water is not necessary (but still dangerous, so the handle carefully).