Is it safe to mix Bleach and sodium hydroxide?

We have explained the famous questions “Is bleach basic” and “How does it affect its commercial and domestic uses”. Let’s learn some chemistry!

Introduction:

Before we get into the details of the question “Is bleach basic”, a quick refresher on the basic chemistry involved in this topic: Bleach goes by many names (Sodium hypochlorite (NaClO), javelle water, liquid bleach, and cleaning bleach) and is a chemical compound often used for cleaning purposes, and the whitening of clothes.

Mostly understood as a common chemical to clean clothes, bleach is much more than when it comes to its industrial uses. Bleaches are of several types, but the most common types are chlorine and oxygen-based bleaches.

Chlorine-based bleaches are those found in fabric-washing agents and are best known for their strong bactericide and disinfectant properties along with the function of whitening fabrics and surfaces. Another prime application is their property to remove stains from clothes. Due to their strong bactericide nature, they are always diluted in water when used in washing products.

The second type is oxygen bleaches which lack chlorine in their molecules and provide oxygen on the surface instead of chorine to remove stains and brighten fabrics. Compared to chlorine, they are safer cleaning agents for colored fabrics and are readily used in today’s detergents and household cleaning agents.

Last but not least, the acidic and basic nature of a solution; as the concentration of hydrogen ions in a solution rises and the concentration of hydroxide ions falls, the solution becomes more acidic. As the concentration of hydroxide ions in solution rises and the concentration of hydrogen ions falls, solutions become more basic.

So, Is Bleach Basic in Chemical Nature?

Yes, bleach is basic (alkaline) in its chemical nature, and here’s why; as mentioned before, bleach is often mixed with water to keep it in a diluted state. In this state, it converts into Na+ ions and OCl^- ions. The OCl^- ions react with the water used to dilute the solution which makes a weak acid in the solution from weak acid HOCl and OH^- ions. Due to the presence of these OH^-, the solution is taken as basic as it contains a high concentration of OH^- ions.

The most common form of bleach you will find in your home will be highly basic with a pH value reaching 13 to 14 after being diluted with water. These ions help the bleach to function as a cleansing agent because the OH^- ions react with proteins, fats, and other materials giving stains to your clothes and washing away them while giving a disinfection effect as well.

Another common strong cleaning agent is lye (potassium carbonate). Both lye and bleach are common materials used in soaps and cleansing products due to their alkaline and anti-bacterial nature.

Is it safe to mix Bleach and sodium hydroxide?

No, the reaction between the two is not considered to be safe due to the emission of chlorine gas and heat. One should take care while conducting this reaction and should arrange proper PPE and suitable experiment environment is maintained.

So how does chlorine is being produced in between the two? Well, sodium hydroxide or NaOH (caustic soda or lye) is a well-known basic compound due to its corrosive and reactive nature along with its various industrial uses. When it is introduced in NaClO, an exothermic reaction happens with the production of water and salt.

NaOH + NaClO → NaCl + NaOCl + H₂O

The NaOCl ions are highly unstable and combine with NaCl to produce sodium chlorate as follows:

NaClO→NaCl+NaClO₃

The sodium chlorate ions further decompose to form chlorine and oxygen gas:

2NaClO₃ → 2NaCl + Cl₂ +3O₂

As indicated above, the reaction results in the formation of pure chlorine gas which can be dangerous to your lung’s inner lining if inhaled for a longer period. Even a short encounter is highly irritant plus the reaction is itself exothermic so is classified as an unsafe reaction. It should be noted that the bleaches in our homes are 90 percent water and the relations with NaOH won’t be extremely dangerous but still care is advised.

Wrapping Up:

To wrap up the question “Is bleach basic”, this conclusion can be established that the reaction between two chemicals is unsafe because of the exothermic nature of the reaction and chlorine gas emission which can permanently damage your respiratory tract.