why is chlorine gas bubbled through concentrated sodium chloride solution?
Chlorine gas is bubbled through concentrated sodium chloride (NaCl) solution to produce sodium hypochlorite (NaClO), which is commonly known as bleach. This process is called chlorination.
To understand why chlorine gas is bubbled through concentrated sodium chloride solution, let's break it down step-by-step:
1. Formation of chlorine gas (Cl₂): Chlorine gas is extracted from a source such as liquid chlorine or sodium hypochlorite by electrolysis. This involves passing an electric current through a solution containing chloride ions (Cl⁻) to produce chlorine gas (Cl₂).
2. Interaction with sodium chloride solution: The produced chlorine gas is then bubbled through a concentrated sodium chloride (NaCl) solution.
3. Chlorine gas and sodium chloride reaction: In the presence of water (H₂O), the chlorine gas reacts with sodium chloride to form sodium hypochlorite (NaClO) and hydrochloric acid (HCl) according to the following equation:
Cl₂ + 2 NaCl + H₂O → 2 NaClO + 2 HCl
This reaction involves the displacement of chlorine gas by chloride ions in sodium chloride to form sodium hypochlorite and hydrochloric acid.
4. Formation of sodium hypochlorite (NaClO): Sodium hypochlorite is the primary active ingredient in bleach, and it acts as a powerful oxidizing agent. It is used for disinfection, cleaning, and bleaching purposes.
So, the bubbling of chlorine gas through concentrated sodium chloride solution is a way to produce sodium hypochlorite, an important chemical compound used in various applications.