Pure Element vs. Compound

Sodium hypochlorite, the active ingredient in bleach, has significantly different properties from pure chlorine (Cl2). Here are some key differences:

1. Chemical Composition:
   - Sodium Hypochlorite (NaOCl): It's a chemical compound containing sodium (Na), oxygen (O), and chlorine (Cl).
   - Pure Chlorine (Cl2): It's a diatomic molecule composed of two chlorine atoms bonded together.

2. Concentration:
   - Sodium Hypochlorite: In household bleach, sodium hypochlorite is typically present at concentrations of 3% to 8.25%.
   - Pure Chlorine: In its gaseous form, chlorine is nearly 100% pure.

3. Reactivity:
   - Sodium Hypochlorite: It's less reactive than pure chlorine gas. Sodium hypochlorite slowly releases chlorine when in solution, which makes it suitable for controlled disinfection and cleaning.
   - Pure Chlorine: Chlorine gas is highly reactive and can be hazardous. It's used in industrial applications for water treatment, sanitation, and chemical synthesis.

4. Toxicity:
   - Sodium Hypochlorite: Household bleach with sodium hypochlorite, while potentially harmful if ingested or inhaled, is less toxic than pure chlorine gas.
   - Pure Chlorine: Chlorine gas is toxic, and exposure to high concentrations can be life-threatening.

5. Use:
   - Sodium Hypochlorite: It's commonly used for household cleaning, disinfection, and laundry. It's also used for water treatment in swimming pools.
   - Pure Chlorine: It's used in industrial processes for disinfection, as a chemical reagent, and for water purification.

6. Stability:
   - Sodium Hypochlorite: It degrades over time, so household bleach should be used within its shelf life.
   - Pure Chlorine: Chlorine gas is relatively stable if stored and handled properly.

7. Safety:
   - Sodium Hypochlorite: It's considered safer for household use due to lower concentrations and stability. However, care should still be taken to avoid mixing it with other chemicals, as this can produce harmful fumes.
   - Pure Chlorine: Chlorine gas is highly toxic and poses greater safety risks.

In summary, sodium hypochlorite in bleach is a milder, less reactive, and more stable form of chlorine compared to pure chlorine gas. It's suitable for common household disinfection and cleaning tasks, while pure chlorine gas is used in industrial and water treatment applications where higher reactivity is required.