How to Prepare a 1000 PPM Sodium Hypochlorite Solution from a 5.2% Concentrated Sodium Hypochlorite Solution

Introduction

Sodium hypochlorite, commonly known as bleach, is a disinfectant frequently used in various applications such as household cleaning, water treatment, and commercial sanitation. One common question that arises is how to prepare a specific concentration of sodium hypochlorite solution from a concentrated stock solution. In this guide, we will walk through the steps to prepare a 1000 parts per million (ppm) sodium hypochlorite solution from a 5.2% (by mass in 100 mL) concentrated sodium hypochlorite solution.

Understanding Concentration

The 5.2% (by mass in 100 mL) sodium hypochlorite solution means that it contains 5.2 grams of sodium hypochlorite in 100 mL of solution. On the other hand, 1000 PPM sodium hypochlorite translates to 1000 mg per liter of solution. To better comprehend the concentrations, 1000 PPM is equivalent to 1000 mg/L, which is the same as 1 gram per liter (1 g/L).

Step-by-Step Guide

Step 1: Understand the Concentrations

It is crucial to understand the initial and final concentrations to proceed with the preparation. The given 5.2% (by mass in 100 mL) solution equates to 52000 mg/L. The target concentration is 1000 mg/L (1000 ppm).

Step 2: Calculate the Dilution Factor

The dilution factor can be calculated using the formula:

C1V1 C2V2

Where:

C1 initial concentration (52000 mg/L) V1 volume of the concentrated solution needed (to be calculated) C2 final concentration (1000 mg/L) V2 final volume of the diluted solution (1000 mL, 1 L)

Rearranging this formula to solve for V1 gives us:

V1 (C2 × V2) / C1

Step 3: Plug in the Values

Using the given values:

V1 (1000 mg/L × 1000 mL) / 52000 mg/L

V1 ≈ 19.23 mL

This calculation shows that approximately 19.23 mL of the 5.2% sodium hypochlorite solution is needed.

Step 4: Prepare the Solution

Measure out 19.23 mL of the 5.2% sodium hypochlorite solution.

Add distilled water to reach a total volume of 1000 mL (1 liter).

Summary: To prepare a 1000 ppm sodium hypochlorite solution, measure approximately 19.23 mL of the 5.2% concentrated sodium hypochlorite solution and dilute it with distilled water to a final volume of 1 liter.

Alternative Methods

A simpler method to achieve this dilution is to recognize that 5.2% corresponds to 52000 ppm. Therefore, to dilute to 1000 ppm, the dilution factor is 52000/1000 52. This means that 1 mL of the 5.2% concentrated sodium hypochlorite solution should be diluted with 51 mL of distilled water to obtain 1000 ppm. Alternatively, 10 mL can be diluted with 520 mL of distilled water.

Cautions and Precautions

Handling sodium hypochlorite safely is paramount. Always wear appropriate personal protective equipment (PPE) such as gloves, goggles, and a lab coat. Work in a well-ventilated area or a fume hood. Proper labeling of the prepared solution is essential for future reference and safety.

Conclusion

By understanding the concentrations and using the proper dilution method, it is straightforward to prepare a 1000 ppm sodium hypochlorite solution from a concentrated 5.2% sodium hypochlorite solution. This process not only ensures the correct solution concentration but also enhances safety in handling and storage.